diff --git a/docs/implementation/task-d54-lead-enquiry-workspace-separation-ui-foundation.md b/docs/implementation/task-d54-lead-enquiry-workspace-separation-ui-foundation.md
new file mode 100644
index 0000000..3d061cb
--- /dev/null
+++ b/docs/implementation/task-d54-lead-enquiry-workspace-separation-ui-foundation.md
@@ -0,0 +1,85 @@
+# Task D.5.4: Lead / Enquiry Workspace Separation UI Foundation
+
+## Objective
+Establish separate CRM workspaces for marketing-owned Leads and sales-owned Enquiries without changing existing quotation, dashboard, reporting, or approval behavior.
+
+## Review Completed
+- `AGENTS.md`
+- `plans/task-d.5.4.md`
+- `docs/standards/project-foundations.md`
+- `docs/standards/task-catalog.md`
+- `docs/adr/0018-lead-enquiry-domain-separation.md`
+- `docs/implementation/task-d5-lead-enquiry-domain-separation.md`
+- `docs/implementation/task-d52-lead-domain-service-api-foundation.md`
+- `docs/implementation/task-d53-lead-assignment-create-enquiry-foundation.md`
+- `docs/security/crm-authorization-boundaries.md`
+- `src/config/nav-config.ts`
+- existing enquiry list, detail, form, and assignment UI
+- existing lead route handlers and lead assignment route
+
+## What Changed
+- Replaced legacy lead route aliases with real lead pages:
+  - [page.tsx](/C:/Users/mtpphtaps/Documents/gitea/alla-allaos-fullstack/src/app/dashboard/crm/leads/page.tsx)
+  - [page.tsx](/C:/Users/mtpphtaps/Documents/gitea/alla-allaos-fullstack/src/app/dashboard/crm/leads/[id]/page.tsx)
+- Added lead client API/query/mutation stack:
+  - [service.ts](/C:/Users/mtpphtaps/Documents/gitea/alla-allaos-fullstack/src/features/crm/leads/api/service.ts)
+  - [queries.ts](/C:/Users/mtpphtaps/Documents/gitea/alla-allaos-fullstack/src/features/crm/leads/api/queries.ts)
+  - [mutations.ts](/C:/Users/mtpphtaps/Documents/gitea/alla-allaos-fullstack/src/features/crm/leads/api/mutations.ts)
+- Added lead UI foundation:
+  - [lead-list.tsx](/C:/Users/mtpphtaps/Documents/gitea/alla-allaos-fullstack/src/features/crm/leads/components/lead-list.tsx)
+  - [leads-table.tsx](/C:/Users/mtpphtaps/Documents/gitea/alla-allaos-fullstack/src/features/crm/leads/components/leads-table.tsx)
+  - [lead-columns.tsx](/C:/Users/mtpphtaps/Documents/gitea/alla-allaos-fullstack/src/features/crm/leads/components/lead-columns.tsx)
+  - [lead-form.tsx](/C:/Users/mtpphtaps/Documents/gitea/alla-allaos-fullstack/src/features/crm/leads/components/lead-form.tsx)
+  - [lead-detail.tsx](/C:/Users/mtpphtaps/Documents/gitea/alla-allaos-fullstack/src/features/crm/leads/components/lead-detail.tsx)
+  - [lead-assignment-dialog.tsx](/C:/Users/mtpphtaps/Documents/gitea/alla-allaos-fullstack/src/features/crm/leads/components/lead-assignment-dialog.tsx)
+  - [lead-followup-panel.tsx](/C:/Users/mtpphtaps/Documents/gitea/alla-allaos-fullstack/src/features/crm/leads/components/lead-followup-panel.tsx)
+- Extended lead domain read models in:
+  - [types.ts](/C:/Users/mtpphtaps/Documents/gitea/alla-allaos-fullstack/src/features/crm/leads/types.ts)
+  - [service.ts](/C:/Users/mtpphtaps/Documents/gitea/alla-allaos-fullstack/src/features/crm/leads/server/service.ts)
+- Lead detail now surfaces:
+  - linked enquiries
+  - assignment result visibility
+  - audit-safe activity list
+  - customer/contact/assignable-user reference data for forms
+- Enquiry detail compatibility updated in [page.tsx](/C:/Users/mtpphtaps/Documents/gitea/alla-allaos-fullstack/src/app/dashboard/crm/enquiries/[id]/page.tsx):
+  - preserves existing enquiry component contract
+  - loads linked lead server-side when `leadId` exists
+  - shows a read-only `Source Lead` block with open-lead navigation
+- Enquiry read DTO now includes `leadId` in:
+  - [types.ts](/C:/Users/mtpphtaps/Documents/gitea/alla-allaos-fullstack/src/features/crm/enquiries/api/types.ts)
+  - [service.ts](/C:/Users/mtpphtaps/Documents/gitea/alla-allaos-fullstack/src/features/crm/enquiries/server/service.ts)
+
+## APIs Consumed
+- `GET /api/crm/leads`
+- `POST /api/crm/leads`
+- `GET /api/crm/leads/[id]`
+- `PATCH /api/crm/leads/[id]`
+- `DELETE /api/crm/leads/[id]`
+- `POST /api/crm/leads/[id]/followups`
+- `POST /api/crm/leads/[id]/assign`
+- existing enquiry detail and follow-up APIs remain unchanged
+
+## Permission Mapping
+- Lead list/detail visibility uses:
+  - `crm.lead.read`
+- Lead create button and create form use:
+  - `crm.lead.create`
+- Lead edit actions use:
+  - `crm.lead.update`
+- Lead delete action uses:
+  - `crm.lead.delete`
+- Lead assignment action uses:
+  - `crm.lead.assign`
+- Enquiry detail compatibility block does not widen enquiry permissions; it only renders when the user can already open the enquiry page.
+
+## Compatibility Notes
+- CRM nav already exposed separate Leads and Enquiries entries, so D.5.4 kept navigation structure and replaced the lead pages behind it.
+- Lead assignment still goes through the D.5.3 server assignment flow and does not create enquiries client-side.
+- Existing enquiry workflow, quotation conversion flow, dashboard datasets, and reports were not changed.
+
+## Known Limitations
+- Lead form intentionally does not introduce a separate persisted `notes` field because D.5.4 is out of scope for schema changes.
+- Lead follow-up entry uses the existing audit-backed foundation and remains compatible with the current D.5.2 persistence approach.
+
+## Verification
+- `npm exec tsc --noEmit`
diff --git a/src/app/api/crm/leads/[id]/assign/route.ts b/src/app/api/crm/leads/[id]/assign/route.ts
index 2868bac..6660ada 100644
--- a/src/app/api/crm/leads/[id]/assign/route.ts
+++ b/src/app/api/crm/leads/[id]/assign/route.ts
@@ -39,7 +39,8 @@ export async function POST(request: NextRequest, { params }: Params) {
       message: 'Lead assigned successfully',
       leadId: result.leadId,
       enquiryId: result.enquiryId,
-      enquiryCode: result.enquiryCode
+      enquiryCode: result.enquiryCode,
+      reusedExistingEnquiry: result.reusedExistingEnquiry
     });
   } catch (error) {
     if (error instanceof AuthError) {
diff --git a/src/app/dashboard/crm/enquiries/[id]/page.tsx b/src/app/dashboard/crm/enquiries/[id]/page.tsx
index 4c99b6d..6fd48a9 100644
--- a/src/app/dashboard/crm/enquiries/[id]/page.tsx
+++ b/src/app/dashboard/crm/enquiries/[id]/page.tsx
@@ -1,13 +1,17 @@
 import { auth } from '@/auth';
 import { HydrationBoundary, dehydrate } from '@tanstack/react-query';
+import { notFound } from 'next/navigation';
+import Link from 'next/link';
 import PageContainer from '@/components/layout/page-container';
+import { Card, CardContent, CardHeader, CardTitle } from '@/components/ui/card';
 import {
   enquiryByIdOptions,
   enquiryFollowupsOptions,
   enquiryProjectPartiesOptions
 } from '@/features/crm/enquiries/api/queries';
 import { EnquiryDetail } from '@/features/crm/enquiries/components/enquiry-detail';
-import { getEnquiryReferenceData } from '@/features/crm/enquiries/server/service';
+import { getEnquiryDetail, getEnquiryReferenceData } from '@/features/crm/enquiries/server/service';
+import { getLeadById } from '@/features/crm/leads/server/service';
 import { listEnquiryQuotationRelations } from '@/features/crm/quotations/server/service';
 import { PERMISSIONS } from '@/lib/auth/rbac';
 import { getQueryClient } from '@/lib/query-client';
@@ -19,117 +23,146 @@ type PageProps = {
 export default async function EnquiryDetailRoute({ params }: PageProps) {
   const { id } = await params;
   const session = await auth();
+
   const canRead =
     session?.user?.systemRole === 'super_admin' ||
     (!!session?.user?.activeOrganizationId &&
       (session.user.activeMembershipRole === 'admin' ||
         session.user.activePermissions.includes(PERMISSIONS.crmEnquiryRead)));
+
   const canUpdate =
     session?.user?.systemRole === 'super_admin' ||
     (!!session?.user?.activeOrganizationId &&
       (session.user.activeMembershipRole === 'admin' ||
         session.user.activePermissions.includes(PERMISSIONS.crmEnquiryUpdate)));
-  const canFollowupCreate =
-    session?.user?.systemRole === 'super_admin' ||
-    (!!session?.user?.activeOrganizationId &&
-      (session.user.activeMembershipRole === 'admin' ||
-        session.user.activePermissions.includes(PERMISSIONS.crmEnquiryFollowupCreate)));
-  const canFollowupUpdate =
-    session?.user?.systemRole === 'super_admin' ||
-    (!!session?.user?.activeOrganizationId &&
-      (session.user.activeMembershipRole === 'admin' ||
-        session.user.activePermissions.includes(PERMISSIONS.crmEnquiryFollowupUpdate)));
-  const canFollowupDelete =
-    session?.user?.systemRole === 'super_admin' ||
-    (!!session?.user?.activeOrganizationId &&
-      (session.user.activeMembershipRole === 'admin' ||
-        session.user.activePermissions.includes(PERMISSIONS.crmEnquiryFollowupDelete)));
+
   const canAssign =
     session?.user?.systemRole === 'super_admin' ||
     (!!session?.user?.activeOrganizationId &&
       (session.user.activeMembershipRole === 'admin' ||
         session.user.activePermissions.includes(PERMISSIONS.crmEnquiryAssign)));
+
   const canReassign =
     session?.user?.systemRole === 'super_admin' ||
     (!!session?.user?.activeOrganizationId &&
       (session.user.activeMembershipRole === 'admin' ||
         session.user.activePermissions.includes(PERMISSIONS.crmEnquiryReassign)));
-  const canReadQuotation =
-    session?.user?.systemRole === 'super_admin' ||
-    (!!session?.user?.activeOrganizationId &&
-      (session.user.activeMembershipRole === 'admin' ||
-        session.user.activePermissions.includes(PERMISSIONS.crmQuotationRead)));
-  const canViewOutcomeCommercialData =
-    session?.user?.systemRole === 'super_admin' ||
-    (!!session?.user?.activeOrganizationId &&
-      (session.user.activeMembershipRole === 'admin' ||
-        session.user.activePermissions.includes(PERMISSIONS.crmQuotationPricingRead)));
+
+  const canManageFollowups = {
+    create:
+      session?.user?.systemRole === 'super_admin' ||
+      (!!session?.user?.activeOrganizationId &&
+        (session.user.activeMembershipRole === 'admin' ||
+          session.user.activePermissions.includes(PERMISSIONS.crmEnquiryFollowupCreate))),
+    update:
+      session?.user?.systemRole === 'super_admin' ||
+      (!!session?.user?.activeOrganizationId &&
+        (session.user.activeMembershipRole === 'admin' ||
+          session.user.activePermissions.includes(PERMISSIONS.crmEnquiryFollowupUpdate))),
+    delete:
+      session?.user?.systemRole === 'super_admin' ||
+      (!!session?.user?.activeOrganizationId &&
+        (session.user.activeMembershipRole === 'admin' ||
+          session.user.activePermissions.includes(PERMISSIONS.crmEnquiryFollowupDelete)))
+  };
+
   const canMarkWon =
     session?.user?.systemRole === 'super_admin' ||
     (!!session?.user?.activeOrganizationId &&
       (session.user.activeMembershipRole === 'admin' ||
         session.user.activePermissions.includes(PERMISSIONS.crmEnquiryMarkWon)));
+
   const canMarkLost =
     session?.user?.systemRole === 'super_admin' ||
     (!!session?.user?.activeOrganizationId &&
       (session.user.activeMembershipRole === 'admin' ||
         session.user.activePermissions.includes(PERMISSIONS.crmEnquiryMarkLost)));
+
   const canReopen =
     session?.user?.systemRole === 'super_admin' ||
     (!!session?.user?.activeOrganizationId &&
       (session.user.activeMembershipRole === 'admin' ||
         session.user.activePermissions.includes(PERMISSIONS.crmEnquiryReopen)));
-  const queryClient = getQueryClient();
 
-  if (canRead) {
-    void queryClient.prefetchQuery(enquiryByIdOptions(id));
-    void queryClient.prefetchQuery(enquiryProjectPartiesOptions(id));
-    void queryClient.prefetchQuery(enquiryFollowupsOptions(id));
+  const canViewRelatedQuotations =
+    session?.user?.systemRole === 'super_admin' ||
+    (!!session?.user?.activeOrganizationId &&
+      (session.user.activeMembershipRole === 'admin' ||
+        session.user.activePermissions.includes(PERMISSIONS.crmQuotationRead)));
+
+  const canViewOutcomeCommercialData = canRead;
+
+  if (!canRead || !session?.user?.activeOrganizationId || !session.user.id) {
+    notFound();
   }
 
-  const referenceData =
-    canRead && session?.user?.activeOrganizationId
-      ? await getEnquiryReferenceData(session.user.activeOrganizationId)
-      : null;
-  const relatedQuotations =
-    canRead && canReadQuotation && session?.user?.activeOrganizationId
-      ? await listEnquiryQuotationRelations(id, session.user.activeOrganizationId)
-      : [];
+  const accessContext = {
+    organizationId: session.user.activeOrganizationId,
+    userId: session.user.id,
+    membershipRole: session.user.activeMembershipRole ?? 'user',
+    businessRole: session.user.activeBusinessRole ?? 'sales_support',
+    businessRoles: [session.user.activeBusinessRole ?? 'sales_support'],
+    permissions: session.user.activePermissions ?? [],
+    branchScopeIds: session.user.activeBranchScopeIds ?? [],
+    productTypeScopeIds: session.user.activeProductTypeScopeIds ?? [],
+    ownershipScope: session.user.activeOwnershipScope ?? 'organization',
+    branchScopeMode: 'all',
+    productScopeMode: 'all',
+    approvalAuthority: null
+  } as const;
+
+  const queryClient = getQueryClient();
+  await Promise.all([
+    queryClient.prefetchQuery(enquiryByIdOptions(id)),
+    queryClient.prefetchQuery(enquiryFollowupsOptions(id)),
+    queryClient.prefetchQuery(enquiryProjectPartiesOptions(id))
+  ]);
+
+  const enquiryDetail = await getEnquiryDetail(id, session.user.activeOrganizationId, accessContext);
+  const [referenceData, relatedQuotations, sourceLead] = await Promise.all([
+    getEnquiryReferenceData(session.user.activeOrganizationId),
+    listEnquiryQuotationRelations(id, session.user.activeOrganizationId),
+    enquiryDetail.leadId
+      ? getLeadById(enquiryDetail.leadId, session.user.activeOrganizationId).catch(() => null)
+      : Promise.resolve(null)
+  ]);
 
   return (
     <PageContainer
       pageTitle='รายละเอียดโอกาสขาย'
-      pageDescription='ข้อมูลโอกาสขาย ไทม์ไลน์การติดตาม และสถานะการดูแลของฝ่ายขาย'
-      access={canRead}
-      accessFallback={
-        <div className='text-muted-foreground rounded-lg border border-dashed p-8 text-center'>
-          You do not have access to this enquiry.
-        </div>
-      }
+      pageDescription='พื้นที่ทำงานของฝ่ายขายสำหรับติดตาม execution ของ enquiry และเชื่อมกับ quotation'
     >
-      {referenceData ? (
-        <HydrationBoundary state={dehydrate(queryClient)}>
-          <EnquiryDetail
-            enquiryId={id}
-            referenceData={referenceData}
-            relatedQuotations={relatedQuotations}
-            workspace='enquiry'
-            canUpdate={canUpdate}
-            canAssign={canAssign}
-            canReassign={canReassign}
-            canViewRelatedQuotations={canReadQuotation}
-            canViewOutcomeCommercialData={canViewOutcomeCommercialData}
-            canMarkWon={canMarkWon}
-            canMarkLost={canMarkLost}
-            canReopen={canReopen}
-            canManageFollowups={{
-              create: canFollowupCreate,
-              update: canFollowupUpdate,
-              delete: canFollowupDelete
-            }}
-          />
-        </HydrationBoundary>
+      {sourceLead ? (
+        <Card className='mb-6'>
+          <CardHeader>
+            <CardTitle>Source Lead</CardTitle>
+          </CardHeader>
+          <CardContent className='text-sm'>
+            <Link href={`/dashboard/crm/leads/${sourceLead.id}`} className='font-medium hover:underline'>
+              {sourceLead.code}
+            </Link>
+            <div className='text-muted-foreground mt-1'>{sourceLead.projectName ?? 'No project name'}</div>
+          </CardContent>
+        </Card>
       ) : null}
+
+      <HydrationBoundary state={dehydrate(queryClient)}>
+        <EnquiryDetail
+          enquiryId={id}
+          referenceData={referenceData}
+          relatedQuotations={relatedQuotations}
+          workspace='enquiry'
+          canUpdate={canUpdate}
+          canAssign={canAssign}
+          canReassign={canReassign}
+          canViewRelatedQuotations={canViewRelatedQuotations}
+          canViewOutcomeCommercialData={canViewOutcomeCommercialData}
+          canMarkWon={canMarkWon}
+          canMarkLost={canMarkLost}
+          canReopen={canReopen}
+          canManageFollowups={canManageFollowups}
+        />
+      </HydrationBoundary>
     </PageContainer>
   );
 }
diff --git a/src/app/dashboard/crm/leads/[id]/page.tsx b/src/app/dashboard/crm/leads/[id]/page.tsx
index ced0db1..2fd2e92 100644
--- a/src/app/dashboard/crm/leads/[id]/page.tsx
+++ b/src/app/dashboard/crm/leads/[id]/page.tsx
@@ -1,14 +1,9 @@
 import { auth } from '@/auth';
 import { HydrationBoundary, dehydrate } from '@tanstack/react-query';
-import { notFound, redirect } from 'next/navigation';
 import PageContainer from '@/components/layout/page-container';
-import {
-  enquiryByIdOptions,
-  enquiryFollowupsOptions,
-  enquiryProjectPartiesOptions
-} from '@/features/crm/enquiries/api/queries';
-import { EnquiryDetail } from '@/features/crm/enquiries/components/enquiry-detail';
-import { getEnquiryDetail, getEnquiryReferenceData } from '@/features/crm/enquiries/server/service';
+import { leadByIdOptions } from '@/features/crm/leads/api/queries';
+import { LeadDetail } from '@/features/crm/leads/components/lead-detail';
+import { getLeadReferenceData } from '@/features/crm/leads/server/service';
 import { PERMISSIONS } from '@/lib/auth/rbac';
 import { getQueryClient } from '@/lib/query-client';
 
@@ -19,91 +14,57 @@ type PageProps = {
 export default async function LeadDetailRoute({ params }: PageProps) {
   const { id } = await params;
   const session = await auth();
+
   const canRead =
     session?.user?.systemRole === 'super_admin' ||
     (!!session?.user?.activeOrganizationId &&
       (session.user.activeMembershipRole === 'admin' ||
         session.user.activePermissions.includes(PERMISSIONS.crmLeadRead)));
+
   const canUpdate =
     session?.user?.systemRole === 'super_admin' ||
     (!!session?.user?.activeOrganizationId &&
       (session.user.activeMembershipRole === 'admin' ||
         session.user.activePermissions.includes(PERMISSIONS.crmLeadUpdate)));
+
+  const canDelete =
+    session?.user?.systemRole === 'super_admin' ||
+    (!!session?.user?.activeOrganizationId &&
+      (session.user.activeMembershipRole === 'admin' ||
+        session.user.activePermissions.includes(PERMISSIONS.crmLeadDelete)));
+
   const canAssign =
     session?.user?.systemRole === 'super_admin' ||
     (!!session?.user?.activeOrganizationId &&
       (session.user.activeMembershipRole === 'admin' ||
         session.user.activePermissions.includes(PERMISSIONS.crmLeadAssign)));
+
+  if (!canRead || !session?.user?.activeOrganizationId) {
+    return (
+      <PageContainer access={false} pageTitle='Lead Detail'>
+        {null}
+      </PageContainer>
+    );
+  }
+
   const queryClient = getQueryClient();
-
-  if (!session?.user?.activeOrganizationId) {
-    notFound();
-  }
-
-  const enquiry = canRead
-    ? await getEnquiryDetail(id, session.user.activeOrganizationId, {
-        organizationId: session.user.activeOrganizationId,
-        userId: session.user.id,
-        membershipRole: session.user.activeMembershipRole ?? 'user',
-        businessRole: session.user.activeBusinessRole ?? 'sales_support',
-        permissions: session.user.activePermissions ?? [],
-        branchScopeIds: session.user.activeBranchScopeIds ?? [],
-        productTypeScopeIds: session.user.activeProductTypeScopeIds ?? [],
-        ownershipScope: session.user.activeOwnershipScope ?? 'organization',
-        branchScopeMode: 'all',
-        productScopeMode: 'all'
-      })
-    : null;
-
-  if (enquiry && enquiry.pipelineStage !== 'lead') {
-    redirect(`/dashboard/crm/enquiries/${id}`);
-  }
-
-  if (canRead) {
-    void queryClient.prefetchQuery(enquiryByIdOptions(id));
-    void queryClient.prefetchQuery(enquiryProjectPartiesOptions(id));
-    void queryClient.prefetchQuery(enquiryFollowupsOptions(id));
-  }
-
-  const referenceData =
-    canRead && session.user.activeOrganizationId
-      ? await getEnquiryReferenceData(session.user.activeOrganizationId)
-      : null;
+  await queryClient.prefetchQuery(leadByIdOptions(id));
+  const referenceData = await getLeadReferenceData(session.user.activeOrganizationId);
 
   return (
     <PageContainer
-      pageTitle='รายละเอียดลีด'
-      pageDescription='ข้อมูลลีดสำหรับการคัดกรอง ติดตาม และส่งต่อให้ฝ่ายขาย'
-      access={canRead}
-      accessFallback={
-        <div className='text-muted-foreground rounded-lg border border-dashed p-8 text-center'>
-          You do not have access to this lead.
-        </div>
-      }
+      pageTitle='Lead Detail'
+      pageDescription='Separated lead workspace for marketing qualification and sales handoff.'
     >
-      {referenceData ? (
-        <HydrationBoundary state={dehydrate(queryClient)}>
-          <EnquiryDetail
-            enquiryId={id}
-            referenceData={referenceData}
-            relatedQuotations={[]}
-            workspace='lead'
-            canUpdate={canUpdate}
-            canAssign={canAssign}
-            canReassign={false}
-            canViewRelatedQuotations={false}
-            canViewOutcomeCommercialData={false}
-            canMarkWon={false}
-            canMarkLost={false}
-            canReopen={false}
-            canManageFollowups={{
-              create: false,
-              update: false,
-              delete: false
-            }}
-          />
-        </HydrationBoundary>
-      ) : null}
+      <HydrationBoundary state={dehydrate(queryClient)}>
+        <LeadDetail
+          leadId={id}
+          referenceData={referenceData}
+          canUpdate={canUpdate}
+          canDelete={canDelete}
+          canAssign={canAssign}
+        />
+      </HydrationBoundary>
     </PageContainer>
   );
 }
diff --git a/src/app/dashboard/crm/leads/page.tsx b/src/app/dashboard/crm/leads/page.tsx
index 9f01135..2a77bdf 100644
--- a/src/app/dashboard/crm/leads/page.tsx
+++ b/src/app/dashboard/crm/leads/page.tsx
@@ -1,14 +1,14 @@
-import { auth } from '@/auth';
-import PageContainer from '@/components/layout/page-container';
-import EnquiryListing from '@/features/crm/enquiries/components/enquiry-listing';
-import { EnquiryFormSheetTrigger } from '@/features/crm/enquiries/components/enquiry-form-sheet';
-import { getEnquiryReferenceData } from '@/features/crm/enquiries/server/service';
-import { PERMISSIONS } from '@/lib/auth/rbac';
-import { searchParamsCache } from '@/lib/searchparams';
-import type { SearchParams } from 'nuqs/server';
+import { auth } from "@/auth";
+import PageContainer from "@/components/layout/page-container";
+import { LeadFormTrigger } from "@/features/crm/leads/components/lead-form";
+import { LeadList } from "@/features/crm/leads/components/lead-list";
+import { getLeadReferenceData } from "@/features/crm/leads/server/service";
+import { PERMISSIONS } from "@/lib/auth/rbac";
+import { searchParamsCache } from "@/lib/searchparams";
+import type { SearchParams } from "nuqs/server";
 
 export const metadata = {
-  title: 'Dashboard: CRM Leads'
+  title: "Dashboard: CRM Leads",
 };
 
 type PageProps = {
@@ -18,63 +18,63 @@ type PageProps = {
 export default async function LeadsRoute(props: PageProps) {
   const searchParams = await props.searchParams;
   const session = await auth();
+
   const canRead =
-    session?.user?.systemRole === 'super_admin' ||
+    session?.user?.systemRole === "super_admin" ||
     (!!session?.user?.activeOrganizationId &&
-      (session.user.activeMembershipRole === 'admin' ||
+      (session.user.activeMembershipRole === "admin" ||
         session.user.activePermissions.includes(PERMISSIONS.crmLeadRead)));
+
   const canCreate =
-    session?.user?.systemRole === 'super_admin' ||
+    session?.user?.systemRole === "super_admin" ||
     (!!session?.user?.activeOrganizationId &&
-      (session.user.activeMembershipRole === 'admin' ||
+      (session.user.activeMembershipRole === "admin" ||
         session.user.activePermissions.includes(PERMISSIONS.crmLeadCreate)));
+
   const canUpdate =
-    session?.user?.systemRole === 'super_admin' ||
+    session?.user?.systemRole === "super_admin" ||
     (!!session?.user?.activeOrganizationId &&
-      (session.user.activeMembershipRole === 'admin' ||
+      (session.user.activeMembershipRole === "admin" ||
         session.user.activePermissions.includes(PERMISSIONS.crmLeadUpdate)));
+
   const canDelete =
-    session?.user?.systemRole === 'super_admin' ||
+    session?.user?.systemRole === "super_admin" ||
     (!!session?.user?.activeOrganizationId &&
-      (session.user.activeMembershipRole === 'admin' ||
+      (session.user.activeMembershipRole === "admin" ||
         session.user.activePermissions.includes(PERMISSIONS.crmLeadDelete)));
+
   const canAssign =
-    session?.user?.systemRole === 'super_admin' ||
+    session?.user?.systemRole === "super_admin" ||
     (!!session?.user?.activeOrganizationId &&
-      (session.user.activeMembershipRole === 'admin' ||
+      (session.user.activeMembershipRole === "admin" ||
         session.user.activePermissions.includes(PERMISSIONS.crmLeadAssign)));
 
+  if (!canRead || !session?.user?.activeOrganizationId) {
+    return (
+      <PageContainer access={false} pageTitle="CRM Leads">
+        {null}
+      </PageContainer>
+    );
+  }
   searchParamsCache.parse(searchParams);
-
-  const referenceData =
-    canRead && session?.user?.activeOrganizationId
-      ? await getEnquiryReferenceData(session.user.activeOrganizationId)
-      : null;
+  const referenceData = await getLeadReferenceData(
+    session.user.activeOrganizationId,
+  );
 
   return (
     <PageContainer
-      pageTitle='ลีด'
-      pageDescription='พื้นที่ทำงานของการตลาดสำหรับเก็บลีด คัดกรองความพร้อม และส่งต่อให้ฝ่ายขาย'
-      access={canRead}
-      accessFallback={
-        <div className='text-muted-foreground rounded-lg border border-dashed p-8 text-center'>
-          You do not have access to CRM leads.
-        </div>
-      }
+      pageTitle="CRM Leads"
+      pageDescription="Marketing-qualified lead workspace before handoff into sales enquiries."
       pageHeaderAction={
-        canCreate && referenceData ? (
-          <EnquiryFormSheetTrigger referenceData={referenceData} workspace='lead' />
-        ) : null
+        canCreate ? <LeadFormTrigger referenceData={referenceData} /> : null
       }
     >
       {referenceData ? (
-        <EnquiryListing
+        <LeadList
           referenceData={referenceData}
-          workspace='lead'
           canUpdate={canUpdate}
           canDelete={canDelete}
           canAssign={canAssign}
-          canReassign={false}
         />
       ) : null}
     </PageContainer>
diff --git a/src/features/crm/enquiries/api/types.ts b/src/features/crm/enquiries/api/types.ts
index dc74832..f34762f 100644
--- a/src/features/crm/enquiries/api/types.ts
+++ b/src/features/crm/enquiries/api/types.ts
@@ -81,6 +81,7 @@ export interface EnquiryRecord {
   id: string;
   organizationId: string;
   branchId: string | null;
+  leadId: string | null;
   code: string;
   customerId: string;
   contactId: string | null;
diff --git a/src/features/crm/enquiries/server/service.ts b/src/features/crm/enquiries/server/service.ts
index c214024..8a3bf68 100644
--- a/src/features/crm/enquiries/server/service.ts
+++ b/src/features/crm/enquiries/server/service.ts
@@ -125,6 +125,7 @@ function mapEnquiryRecord(
     id: row.id,
     organizationId: row.organizationId,
     branchId: row.branchId,
+    leadId: row.leadId ?? null,
     code: row.code,
     customerId: row.customerId,
     contactId: row.contactId,
diff --git a/src/features/crm/leads/api/mutations.ts b/src/features/crm/leads/api/mutations.ts
new file mode 100644
index 0000000..d3374b9
--- /dev/null
+++ b/src/features/crm/leads/api/mutations.ts
@@ -0,0 +1,75 @@
+import { mutationOptions } from '@tanstack/react-query';
+import { getQueryClient } from '@/lib/query-client';
+import { assignLead, createLead, createLeadFollowup, deleteLead, updateLead } from './service';
+import { leadKeys } from './queries';
+import type { CreateLeadFollowupInput, CreateLeadInput, UpdateLeadInput } from './types';
+
+async function invalidateLeadLists() {
+  await getQueryClient().invalidateQueries({ queryKey: leadKeys.lists() });
+}
+
+async function invalidateLeadDetail(id: string) {
+  await getQueryClient().invalidateQueries({ queryKey: leadKeys.detail(id) });
+}
+
+export async function invalidateLeadMutationQueries(id: string) {
+  await Promise.all([invalidateLeadLists(), invalidateLeadDetail(id)]);
+}
+
+export const createLeadMutation = mutationOptions({
+  mutationFn: (values: CreateLeadInput) => createLead(values),
+  onSettled: async (data, error) => {
+    if (!error && data?.lead?.id) {
+      await invalidateLeadMutationQueries(data.lead.id);
+      return;
+    }
+
+    if (!error) {
+      await invalidateLeadLists();
+    }
+  }
+});
+
+export const updateLeadMutation = mutationOptions({
+  mutationFn: ({ id, values }: { id: string; values: UpdateLeadInput }) => updateLead(id, values),
+  onSettled: async (_data, error, variables) => {
+    if (!error) {
+      await invalidateLeadMutationQueries(variables.id);
+    }
+  }
+});
+
+export const deleteLeadMutation = mutationOptions({
+  mutationFn: ({ id }: { id: string }) => deleteLead(id),
+  onSettled: async (_data, error, variables) => {
+    if (!error) {
+      await invalidateLeadLists();
+      getQueryClient().removeQueries({ queryKey: leadKeys.detail(variables.id) });
+    }
+  }
+});
+
+export const createLeadFollowupMutation = mutationOptions({
+  mutationFn: ({ leadId, values }: { leadId: string; values: CreateLeadFollowupInput }) =>
+    createLeadFollowup(leadId, values),
+  onSettled: async (_data, error, variables) => {
+    if (!error) {
+      await invalidateLeadDetail(variables.leadId);
+    }
+  }
+});
+
+export const assignLeadMutation = mutationOptions({
+  mutationFn: ({
+    leadId,
+    values
+  }: {
+    leadId: string;
+    values: { salesOwnerId: string; assignmentRemark?: string | null };
+  }) => assignLead(leadId, values),
+  onSettled: async (_data, error, variables) => {
+    if (!error) {
+      await invalidateLeadMutationQueries(variables.leadId);
+    }
+  }
+});
diff --git a/src/features/crm/leads/api/queries.ts b/src/features/crm/leads/api/queries.ts
new file mode 100644
index 0000000..f13a800
--- /dev/null
+++ b/src/features/crm/leads/api/queries.ts
@@ -0,0 +1,23 @@
+import { queryOptions } from '@tanstack/react-query';
+import { getLeadById, getLeads } from './service';
+import type { LeadListFilters } from './types';
+
+export const leadKeys = {
+  all: ['crm-leads'] as const,
+  lists: () => [...leadKeys.all, 'list'] as const,
+  list: (filters: LeadListFilters) => [...leadKeys.lists(), filters] as const,
+  details: () => [...leadKeys.all, 'detail'] as const,
+  detail: (id: string) => [...leadKeys.details(), id] as const
+};
+
+export const leadsQueryOptions = (filters: LeadListFilters) =>
+  queryOptions({
+    queryKey: leadKeys.list(filters),
+    queryFn: () => getLeads(filters)
+  });
+
+export const leadByIdOptions = (id: string) =>
+  queryOptions({
+    queryKey: leadKeys.detail(id),
+    queryFn: () => getLeadById(id)
+  });
diff --git a/src/features/crm/leads/api/service.ts b/src/features/crm/leads/api/service.ts
new file mode 100644
index 0000000..0d98f6d
--- /dev/null
+++ b/src/features/crm/leads/api/service.ts
@@ -0,0 +1,79 @@
+import { apiClient } from '@/lib/api-client';
+import type {
+  AssignLeadResult,
+  CreateLeadFollowupInput,
+  CreateLeadInput,
+  LeadDetailResponse,
+  LeadListFilters,
+  LeadListResponse,
+  LeadMutationSuccessResponse,
+  UpdateLeadInput
+} from './types';
+
+export async function getLeads(filters: LeadListFilters): Promise<LeadListResponse> {
+  const searchParams = new URLSearchParams();
+
+  if (filters.page) searchParams.set('page', String(filters.page));
+  if (filters.limit) searchParams.set('limit', String(filters.limit));
+  if (filters.search) searchParams.set('search', filters.search);
+  if (filters.branchId) searchParams.set('branchId', filters.branchId);
+  if (filters.customerId) searchParams.set('customerId', filters.customerId);
+  if (filters.status) searchParams.set('status', filters.status);
+  if (filters.awarenessId) searchParams.set('awarenessId', filters.awarenessId);
+  if (filters.followupStatus) searchParams.set('followupStatus', filters.followupStatus);
+  if (filters.outcome) searchParams.set('outcome', filters.outcome);
+  if (filters.ownerMarketingUserId) {
+    searchParams.set('ownerMarketingUserId', filters.ownerMarketingUserId);
+  }
+  if (filters.sort) searchParams.set('sort', filters.sort);
+
+  const query = searchParams.toString();
+  return apiClient<LeadListResponse>(`/crm/leads${query ? `?${query}` : ''}`);
+}
+
+export async function getLeadById(id: string): Promise<LeadDetailResponse> {
+  return apiClient<LeadDetailResponse>(`/crm/leads/${id}`);
+}
+
+export async function createLead(data: CreateLeadInput): Promise<LeadMutationSuccessResponse> {
+  return apiClient<LeadMutationSuccessResponse>('/crm/leads', {
+    method: 'POST',
+    body: JSON.stringify(data)
+  });
+}
+
+export async function updateLead(
+  id: string,
+  data: UpdateLeadInput
+): Promise<LeadMutationSuccessResponse> {
+  return apiClient<LeadMutationSuccessResponse>(`/crm/leads/${id}`, {
+    method: 'PATCH',
+    body: JSON.stringify(data)
+  });
+}
+
+export async function deleteLead(id: string): Promise<LeadMutationSuccessResponse> {
+  return apiClient<LeadMutationSuccessResponse>(`/crm/leads/${id}`, {
+    method: 'DELETE'
+  });
+}
+
+export async function createLeadFollowup(
+  leadId: string,
+  data: CreateLeadFollowupInput
+): Promise<LeadMutationSuccessResponse> {
+  return apiClient<LeadMutationSuccessResponse>(`/crm/leads/${leadId}/followups`, {
+    method: 'POST',
+    body: JSON.stringify(data)
+  });
+}
+
+export async function assignLead(
+  leadId: string,
+  data: { salesOwnerId: string; assignmentRemark?: string | null }
+): Promise<AssignLeadResult> {
+  return apiClient<AssignLeadResult>(`/crm/leads/${leadId}/assign`, {
+    method: 'POST',
+    body: JSON.stringify(data)
+  });
+}
diff --git a/src/features/crm/leads/api/types.ts b/src/features/crm/leads/api/types.ts
new file mode 100644
index 0000000..03de2cc
--- /dev/null
+++ b/src/features/crm/leads/api/types.ts
@@ -0,0 +1,20 @@
+export type {
+  AssignLeadInput,
+  AssignLeadResult,
+  CreateLeadFollowupInput,
+  CreateLeadInput,
+  LeadActivityRecord,
+  LeadAssignableUserLookup,
+  LeadBranchOption,
+  LeadDetail,
+  LeadDetailResponse,
+  LeadFollowupSummary,
+  LeadLinkedEnquirySummary,
+  LeadListFilters,
+  LeadListResponse,
+  LeadMutationSuccessResponse,
+  LeadOption,
+  LeadReferenceData,
+  LeadSummary,
+  UpdateLeadInput
+} from '../types';
diff --git a/src/features/crm/leads/components/lead-assignment-dialog.tsx b/src/features/crm/leads/components/lead-assignment-dialog.tsx
new file mode 100644
index 0000000..e10738e
--- /dev/null
+++ b/src/features/crm/leads/components/lead-assignment-dialog.tsx
@@ -0,0 +1,149 @@
+'use client';
+
+import { useEffect, useMemo } from 'react';
+import Link from 'next/link';
+import { useMutation } from '@tanstack/react-query';
+import { toast } from 'sonner';
+import { Button } from '@/components/ui/button';
+import {
+  Dialog,
+  DialogContent,
+  DialogDescription,
+  DialogFooter,
+  DialogHeader,
+  DialogTitle
+} from '@/components/ui/dialog';
+import { useAppForm, useFormFields } from '@/components/ui/tanstack-form';
+import type { LeadDetail, LeadReferenceData, LeadSummary } from '../api/types';
+import { assignLeadMutation } from '../api/mutations';
+
+type AssignmentFormValues = {
+  salesOwnerId: string;
+  assignmentRemark: string | null;
+};
+
+function toDefaultValues(
+  lead: LeadSummary | LeadDetail,
+  referenceData: LeadReferenceData
+): AssignmentFormValues {
+  return {
+    salesOwnerId:
+      lead.assignedSalesOwnerId ??
+      lead.suggestedSalesOwnerId ??
+      referenceData.assignableUsers[0]?.id ??
+      '',
+    assignmentRemark: lead.assignmentRemark ?? null
+  };
+}
+
+export function LeadAssignmentDialog({
+  lead,
+  referenceData,
+  open,
+  onOpenChange
+}: {
+  lead: LeadSummary | LeadDetail;
+  referenceData: LeadReferenceData;
+  open: boolean;
+  onOpenChange: (open: boolean) => void;
+}) {
+  const defaultValues = useMemo(() => toDefaultValues(lead, referenceData), [lead, referenceData]);
+  const { FormSelectField, FormTextareaField } = useFormFields<AssignmentFormValues>();
+
+  const mutation = useMutation({
+    ...assignLeadMutation,
+    onSuccess: (result) => {
+      toast.success(
+        result.reusedExistingEnquiry
+          ? `มอบหมายสำเร็จและใช้ enquiry เดิม ${result.enquiryCode}`
+          : `มอบหมายสำเร็จและสร้าง enquiry ${result.enquiryCode}`
+      );
+      onOpenChange(false);
+    },
+    onError: (error) => {
+      toast.error(error instanceof Error ? error.message : 'ไม่สามารถมอบหมายลีดได้');
+    }
+  });
+
+  const form = useAppForm({
+    defaultValues,
+    onSubmit: async ({ value }) => {
+      await mutation.mutateAsync({
+        leadId: lead.id,
+        values: {
+          salesOwnerId: value.salesOwnerId,
+          assignmentRemark: value.assignmentRemark || null
+        }
+      });
+    }
+  });
+
+  useEffect(() => {
+    if (open) {
+      form.reset(defaultValues);
+    }
+  }, [defaultValues, form, open]);
+
+  return (
+    <Dialog open={open} onOpenChange={onOpenChange}>
+      <DialogContent>
+        <DialogHeader>
+          <DialogTitle>Assign Lead to Sales</DialogTitle>
+          <DialogDescription>
+            มอบหมายลีดให้ฝ่ายขายและสร้าง enquiry workspace แยกจาก lead workspace
+          </DialogDescription>
+        </DialogHeader>
+
+        <form.AppForm>
+          <form.Form id='lead-assignment-form' className='space-y-4'>
+            <FormSelectField
+              name='salesOwnerId'
+              label='Sales Owner'
+              options={referenceData.assignableUsers.map((user) => ({
+                value: user.id,
+                label: user.name
+              }))}
+            />
+            <FormTextareaField
+              name='assignmentRemark'
+              label='Assignment Remark'
+              placeholder='Optional handoff context for sales'
+            />
+          </form.Form>
+        </form.AppForm>
+
+        {lead.suggestedSalesOwnerName ? (
+          <div className='text-muted-foreground text-sm'>
+            Suggested customer owner: {lead.suggestedSalesOwnerName}
+          </div>
+        ) : null}
+
+        <DialogFooter>
+          <Button variant='outline' onClick={() => onOpenChange(false)} disabled={mutation.isPending}>
+            Cancel
+          </Button>
+          <Button type='submit' form='lead-assignment-form' isLoading={mutation.isPending}>
+            Assign
+          </Button>
+        </DialogFooter>
+
+        {'linkedEnquiries' in lead && lead.linkedEnquiries.length > 0 ? (
+          <div className='border-border rounded-md border p-3 text-sm'>
+            <div className='mb-2 font-medium'>Linked enquiries</div>
+            <div className='space-y-1'>
+              {lead.linkedEnquiries.map((enquiry) => (
+                <Link
+                  key={enquiry.id}
+                  href={`/dashboard/crm/enquiries/${enquiry.id}`}
+                  className='block hover:underline'
+                >
+                  {enquiry.code} - {enquiry.title}
+                </Link>
+              ))}
+            </div>
+          </div>
+        ) : null}
+      </DialogContent>
+    </Dialog>
+  );
+}
diff --git a/src/features/crm/leads/components/lead-cell-action.tsx b/src/features/crm/leads/components/lead-cell-action.tsx
new file mode 100644
index 0000000..9793ef3
--- /dev/null
+++ b/src/features/crm/leads/components/lead-cell-action.tsx
@@ -0,0 +1,91 @@
+'use client';
+
+import { useState } from 'react';
+import { useMutation } from '@tanstack/react-query';
+import { toast } from 'sonner';
+import { Icons } from '@/components/icons';
+import { AlertModal } from '@/components/modal/alert-modal';
+import { Button } from '@/components/ui/button';
+import {
+  DropdownMenu,
+  DropdownMenuContent,
+  DropdownMenuItem,
+  DropdownMenuLabel,
+  DropdownMenuTrigger
+} from '@/components/ui/dropdown-menu';
+import { deleteLeadMutation } from '../api/mutations';
+import type { LeadReferenceData, LeadSummary } from '../api/types';
+import { LeadAssignmentDialog } from './lead-assignment-dialog';
+import { LeadForm } from './lead-form';
+
+export function LeadCellAction({
+  data,
+  referenceData,
+  canUpdate,
+  canDelete,
+  canAssign
+}: {
+  data: LeadSummary;
+  referenceData: LeadReferenceData;
+  canUpdate: boolean;
+  canDelete: boolean;
+  canAssign: boolean;
+}) {
+  const [deleteOpen, setDeleteOpen] = useState(false);
+  const [editOpen, setEditOpen] = useState(false);
+  const [assignOpen, setAssignOpen] = useState(false);
+
+  const deleteMutation = useMutation({
+    ...deleteLeadMutation,
+    onSuccess: () => {
+      toast.success('ลบลีดสำเร็จ');
+      setDeleteOpen(false);
+    },
+    onError: (error) => {
+      toast.error(error instanceof Error ? error.message : 'ไม่สามารถลบลีดได้');
+    }
+  });
+
+  return (
+    <>
+      <LeadForm open={editOpen} onOpenChange={setEditOpen} referenceData={referenceData} lead={data} />
+      <LeadAssignmentDialog
+        lead={data}
+        referenceData={referenceData}
+        open={assignOpen}
+        onOpenChange={setAssignOpen}
+      />
+      <AlertModal
+        isOpen={deleteOpen}
+        onClose={() => setDeleteOpen(false)}
+        onConfirm={() => deleteMutation.mutate({ id: data.id })}
+        loading={deleteMutation.isPending}
+      />
+
+      <DropdownMenu modal={false}>
+        <DropdownMenuTrigger asChild>
+          <Button variant='ghost' className='h-8 w-8 p-0'>
+            <span className='sr-only'>Open menu</span>
+            <Icons.ellipsis className='h-4 w-4' />
+          </Button>
+        </DropdownMenuTrigger>
+        <DropdownMenuContent align='end'>
+          <DropdownMenuLabel>Actions</DropdownMenuLabel>
+          {canUpdate ? (
+            <DropdownMenuItem onClick={() => setEditOpen(true)}>Edit lead</DropdownMenuItem>
+          ) : null}
+          {canAssign ? (
+            <DropdownMenuItem onClick={() => setAssignOpen(true)}>
+              {data.assignedSalesOwnerId ? 'Reassign to sales' : 'Assign to sales'}
+            </DropdownMenuItem>
+          ) : null}
+          {canDelete ? (
+            <DropdownMenuItem className='text-destructive' onClick={() => setDeleteOpen(true)}>
+              Delete lead
+            </DropdownMenuItem>
+          ) : null}
+        </DropdownMenuContent>
+      </DropdownMenu>
+    </>
+  );
+}
diff --git a/src/features/crm/leads/components/lead-columns.tsx b/src/features/crm/leads/components/lead-columns.tsx
new file mode 100644
index 0000000..3c534da
--- /dev/null
+++ b/src/features/crm/leads/components/lead-columns.tsx
@@ -0,0 +1,164 @@
+'use client';
+
+import Link from 'next/link';
+import type { Column, ColumnDef } from '@tanstack/react-table';
+import { Icons } from '@/components/icons';
+import { Badge } from '@/components/ui/badge';
+import { DataTableColumnHeader } from '@/components/ui/table/data-table-column-header';
+import type { LeadReferenceData, LeadSummary } from '../api/types';
+import { LeadCellAction } from './lead-cell-action';
+
+export function getLeadColumns({
+  referenceData,
+  canUpdate,
+  canDelete,
+  canAssign
+}: {
+  referenceData: LeadReferenceData;
+  canUpdate: boolean;
+  canDelete: boolean;
+  canAssign: boolean;
+}): ColumnDef<LeadSummary>[] {
+  return [
+    {
+      id: 'code',
+      accessorKey: 'code',
+      header: ({ column }: { column: Column<LeadSummary, unknown> }) => (
+        <DataTableColumnHeader column={column} title='Lead Code' />
+      ),
+      cell: ({ row }) => (
+        <div className='flex flex-col'>
+          <Link href={`/dashboard/crm/leads/${row.original.id}`} className='font-medium hover:underline'>
+            {row.original.code}
+          </Link>
+          <span className='text-muted-foreground text-xs'>{row.original.customerName ?? '-'}</span>
+        </div>
+      ),
+      meta: {
+        label: 'Lead Code',
+        placeholder: 'Search leads...',
+        variant: 'text' as const,
+        icon: Icons.search
+      },
+      enableColumnFilter: true
+    },
+    {
+      id: 'status',
+      accessorFn: (row) => row.status,
+      header: ({ column }: { column: Column<LeadSummary, unknown> }) => (
+        <DataTableColumnHeader column={column} title='Status' />
+      ),
+      cell: ({ row }) => <Badge variant='outline'>{row.original.statusLabel ?? row.original.status}</Badge>,
+      meta: {
+        label: 'Status',
+        variant: 'select' as const,
+        options: referenceData.statuses.map((item) => ({
+          label: item.label,
+          value: item.id
+        }))
+      },
+      enableColumnFilter: true
+    },
+    {
+      id: 'branchId',
+      accessorFn: (row) => row.branchId ?? '',
+      header: ({ column }: { column: Column<LeadSummary, unknown> }) => (
+        <DataTableColumnHeader column={column} title='Branch' />
+      ),
+      cell: ({ row }) => {
+        const branch = referenceData.branches.find((item) => item.id === row.original.branchId);
+        return <span>{branch?.name ?? '-'}</span>;
+      },
+      meta: {
+        label: 'Branch',
+        variant: 'select' as const,
+        options: referenceData.branches.map((item) => ({
+          label: item.name,
+          value: item.id
+        }))
+      },
+      enableColumnFilter: true
+    },
+    {
+      id: 'customerId',
+      accessorFn: (row) => row.customerId ?? '',
+      header: ({ column }: { column: Column<LeadSummary, unknown> }) => (
+        <DataTableColumnHeader column={column} title='Customer' />
+      ),
+      cell: ({ row }) => <span>{row.original.customerName ?? '-'}</span>,
+      meta: {
+        label: 'Customer',
+        variant: 'select' as const,
+        options: referenceData.customers.map((item) => ({
+          label: `${item.name} (${item.code})`,
+          value: item.id
+        }))
+      },
+      enableColumnFilter: true
+    },
+    {
+      id: 'projectName',
+      accessorKey: 'projectName',
+      header: ({ column }: { column: Column<LeadSummary, unknown> }) => (
+        <DataTableColumnHeader column={column} title='Project' />
+      ),
+      cell: ({ row }) => <span>{row.original.projectName ?? '-'}</span>
+    },
+    {
+      id: 'priority',
+      accessorFn: (row) => row.priority ?? '',
+      header: ({ column }: { column: Column<LeadSummary, unknown> }) => (
+        <DataTableColumnHeader column={column} title='Priority' />
+      ),
+      cell: ({ row }) => <span>{row.original.priority ?? '-'}</span>
+    },
+    {
+      id: 'suggestedSalesOwner',
+      accessorFn: (row) => row.suggestedSalesOwnerId ?? '',
+      header: ({ column }: { column: Column<LeadSummary, unknown> }) => (
+        <DataTableColumnHeader column={column} title='Suggested Owner' />
+      ),
+      cell: ({ row }) => <span>{row.original.suggestedSalesOwnerName ?? '-'}</span>
+    },
+    {
+      id: 'assignedSalesOwner',
+      accessorFn: (row) => row.assignedSalesOwnerId ?? '',
+      header: ({ column }: { column: Column<LeadSummary, unknown> }) => (
+        <DataTableColumnHeader column={column} title='Assigned Owner' />
+      ),
+      cell: ({ row }) => <span>{row.original.assignedSalesOwnerName ?? '-'}</span>
+    },
+    {
+      id: 'estimatedValue',
+      accessorKey: 'estimatedValue',
+      header: ({ column }: { column: Column<LeadSummary, unknown> }) => (
+        <DataTableColumnHeader column={column} title='Estimated Value' />
+      ),
+      cell: ({ row }) => (
+        <span>
+          {row.original.estimatedValue !== null ? row.original.estimatedValue.toLocaleString() : '-'}
+        </span>
+      )
+    },
+    {
+      id: 'createdAt',
+      accessorKey: 'createdAt',
+      header: ({ column }: { column: Column<LeadSummary, unknown> }) => (
+        <DataTableColumnHeader column={column} title='Created' />
+      ),
+      cell: ({ row }) => <span>{new Date(row.original.createdAt).toLocaleDateString()}</span>
+    },
+    {
+      id: 'actions',
+      cell: ({ row }) => (
+        <LeadCellAction
+          data={row.original}
+          referenceData={referenceData}
+          canUpdate={canUpdate}
+          canDelete={canDelete}
+          canAssign={canAssign}
+        />
+      )
+    }
+  ];
+}
diff --git a/src/features/crm/leads/components/lead-detail.tsx b/src/features/crm/leads/components/lead-detail.tsx
new file mode 100644
index 0000000..1b04039
--- /dev/null
+++ b/src/features/crm/leads/components/lead-detail.tsx
@@ -0,0 +1,190 @@
+'use client';
+
+import Link from 'next/link';
+import { useState } from 'react';
+import { useSuspenseQuery } from '@tanstack/react-query';
+import { Badge } from '@/components/ui/badge';
+import { Button } from '@/components/ui/button';
+import { Card, CardContent, CardHeader, CardTitle } from '@/components/ui/card';
+import { Tabs, TabsContent, TabsList, TabsTrigger } from '@/components/ui/tabs';
+import { leadByIdOptions } from '../api/queries';
+import type { LeadReferenceData } from '../api/types';
+import { LeadAssignmentDialog } from './lead-assignment-dialog';
+import { LeadFollowupPanel } from './lead-followup-panel';
+import { LeadForm } from './lead-form';
+
+function FieldItem({ label, value }: { label: string; value: string | null | undefined }) {
+  return (
+    <div className='space-y-1'>
+      <div className='text-muted-foreground text-xs'>{label}</div>
+      <div className='text-sm'>{value || '-'}</div>
+    </div>
+  );
+}
+
+export function LeadDetail({
+  leadId,
+  referenceData,
+  canUpdate,
+  canDelete,
+  canAssign
+}: {
+  leadId: string;
+  referenceData: LeadReferenceData;
+  canUpdate: boolean;
+  canDelete: boolean;
+  canAssign: boolean;
+}) {
+  const { data } = useSuspenseQuery(leadByIdOptions(leadId));
+  const lead = data.lead;
+  const [editOpen, setEditOpen] = useState(false);
+  const [assignOpen, setAssignOpen] = useState(false);
+
+  return (
+    <div className='space-y-6'>
+      <LeadForm open={editOpen} onOpenChange={setEditOpen} referenceData={referenceData} lead={lead} />
+      <LeadAssignmentDialog
+        lead={lead}
+        referenceData={referenceData}
+        open={assignOpen}
+        onOpenChange={setAssignOpen}
+      />
+
+      <div className='flex items-start justify-between gap-4'>
+        <div>
+          <div className='flex items-center gap-3'>
+            <h2 className='text-2xl font-semibold'>{lead.code}</h2>
+            <Badge variant='outline'>{lead.statusLabel ?? lead.status}</Badge>
+          </div>
+          <p className='text-muted-foreground mt-2 text-sm'>
+            Lead workspace for marketing qualification before sales enquiry handoff
+          </p>
+        </div>
+
+        <div className='flex flex-wrap gap-2'>
+          {canAssign ? (
+            <Button variant='outline' onClick={() => setAssignOpen(true)}>
+              {lead.assignedSalesOwnerId ? 'Reassign to Sales' : 'Assign to Sales'}
+            </Button>
+          ) : null}
+          {canUpdate ? (
+            <Button variant='outline' onClick={() => setEditOpen(true)}>
+              Edit Lead
+            </Button>
+          ) : null}
+        </div>
+      </div>
+
+      <div className='grid gap-6 lg:grid-cols-3'>
+        <div className='space-y-6 lg:col-span-2'>
+          <Card>
+            <CardHeader>
+              <CardTitle>Lead Summary</CardTitle>
+            </CardHeader>
+            <CardContent className='grid gap-4 md:grid-cols-2 xl:grid-cols-3'>
+              <FieldItem label='Customer' value={lead.customerName} />
+              <FieldItem label='Contact' value={lead.contactName} />
+              <FieldItem label='Project Name' value={lead.projectName} />
+              <FieldItem label='Project Location' value={lead.projectLocation} />
+              <FieldItem label='Awareness' value={lead.awarenessLabel} />
+              <FieldItem label='Priority' value={lead.priority} />
+              <FieldItem label='Marketing Owner' value={lead.ownerMarketingName} />
+              <FieldItem label='Suggested Sales Owner' value={lead.suggestedSalesOwnerName} />
+              <FieldItem label='Assigned Sales Owner' value={lead.assignedSalesOwnerName} />
+              <FieldItem
+                label='Estimated Value'
+                value={lead.estimatedValue !== null ? lead.estimatedValue.toLocaleString() : null}
+              />
+              <FieldItem label='Assignment Remark' value={lead.assignmentRemark} />
+              <FieldItem label='Description' value={lead.description} />
+            </CardContent>
+          </Card>
+
+          <Tabs defaultValue='followups' className='space-y-4'>
+            <TabsList>
+              <TabsTrigger value='followups'>Follow-ups</TabsTrigger>
+              <TabsTrigger value='linked-enquiries'>Linked Enquiries</TabsTrigger>
+              <TabsTrigger value='activity'>Activity</TabsTrigger>
+            </TabsList>
+
+            <TabsContent value='followups'>
+              <LeadFollowupPanel leadId={leadId} detail={data} />
+            </TabsContent>
+
+            <TabsContent value='linked-enquiries'>
+              <Card>
+                <CardHeader>
+                  <CardTitle>Linked Enquiries</CardTitle>
+                </CardHeader>
+                <CardContent className='space-y-3'>
+                  {lead.linkedEnquiries.length === 0 ? (
+                    <div className='text-muted-foreground text-sm'>No linked enquiries yet.</div>
+                  ) : (
+                    lead.linkedEnquiries.map((enquiry) => (
+                      <div key={enquiry.id} className='border-border rounded-md border p-3'>
+                        <div className='flex items-center justify-between gap-3'>
+                          <Link
+                            href={`/dashboard/crm/enquiries/${enquiry.id}`}
+                            className='font-medium hover:underline'
+                          >
+                            {enquiry.code}
+                          </Link>
+                          <Badge variant='outline'>{enquiry.status}</Badge>
+                        </div>
+                        <div className='mt-1 text-sm'>{enquiry.title}</div>
+                        <div className='text-muted-foreground mt-2 text-xs'>
+                          Owner: {enquiry.assignedToName ?? '-'}
+                        </div>
+                      </div>
+                    ))
+                  )}
+                </CardContent>
+              </Card>
+            </TabsContent>
+
+            <TabsContent value='activity'>
+              <Card>
+                <CardHeader>
+                  <CardTitle>Activity</CardTitle>
+                </CardHeader>
+                <CardContent className='space-y-3'>
+                  {lead.activity.length === 0 ? (
+                    <div className='text-muted-foreground text-sm'>No activity yet.</div>
+                  ) : (
+                    lead.activity.map((activity) => (
+                      <div key={activity.id} className='border-border rounded-md border p-3'>
+                        <div className='font-medium'>{activity.action}</div>
+                        <div className='text-muted-foreground mt-1 text-xs'>
+                          {activity.actorName ?? activity.userId} -{' '}
+                          {new Date(activity.createdAt).toLocaleString()}
+                        </div>
+                      </div>
+                    ))
+                  )}
+                </CardContent>
+              </Card>
+            </TabsContent>
+          </Tabs>
+        </div>
+
+        <div className='space-y-6'>
+          <Card>
+            <CardHeader>
+              <CardTitle>Workspace Status</CardTitle>
+            </CardHeader>
+            <CardContent className='space-y-3'>
+              <FieldItem label='Current Workspace' value='Lead' />
+              <FieldItem label='Related Enquiries' value={String(lead.relatedEnquiryCount)} />
+              <FieldItem
+                label='Assigned At'
+                value={lead.assignedAt ? new Date(lead.assignedAt).toLocaleString() : null}
+              />
+              <FieldItem label='Assigned By' value={lead.assignedByName} />
+              <FieldItem label='Deleted' value={canDelete ? 'Allowed' : 'Not allowed'} />
+            </CardContent>
+          </Card>
+        </div>
+      </div>
+    </div>
+  );
+}
diff --git a/src/features/crm/leads/components/lead-followup-panel.tsx b/src/features/crm/leads/components/lead-followup-panel.tsx
new file mode 100644
index 0000000..18f4fcd
--- /dev/null
+++ b/src/features/crm/leads/components/lead-followup-panel.tsx
@@ -0,0 +1,120 @@
+'use client';
+
+import { useMutation } from '@tanstack/react-query';
+import { toast } from 'sonner';
+import { Button } from '@/components/ui/button';
+import { Card, CardContent, CardHeader, CardTitle } from '@/components/ui/card';
+import { useAppForm, useFormFields } from '@/components/ui/tanstack-form';
+import type { LeadDetailResponse } from '../api/types';
+import { createLeadFollowupMutation } from '../api/mutations';
+
+type FollowupFormValues = {
+  followupDate: string;
+  followupStatus: string;
+  note: string | null;
+  nextFollowupDate: string | null;
+};
+
+export function LeadFollowupPanel({
+  leadId,
+  detail
+}: {
+  leadId: string;
+  detail: LeadDetailResponse;
+}) {
+  const { FormTextField, FormSelectField, FormTextareaField } = useFormFields<FollowupFormValues>();
+
+  const form = useAppForm({
+    defaultValues: {
+      followupDate: '',
+      followupStatus: detail.referenceData.followupStatuses[0]?.id ?? '',
+      note: null,
+      nextFollowupDate: null
+    },
+    onSubmit: async ({ value }) => {
+      await mutation.mutateAsync({
+        leadId,
+        values: {
+          followupDate: value.followupDate,
+          followupStatus: value.followupStatus,
+          note: value.note || null,
+          nextFollowupDate: value.nextFollowupDate || null
+        }
+      });
+    }
+  });
+
+  const mutation = useMutation({
+    ...createLeadFollowupMutation,
+    onSuccess: () => {
+      toast.success('บันทึก follow-up สำเร็จ');
+      form.reset();
+    },
+    onError: (error) => {
+      toast.error(error instanceof Error ? error.message : 'ไม่สามารถบันทึก follow-up ได้');
+    }
+  });
+
+  return (
+    <div className='space-y-4'>
+      <Card>
+        <CardHeader>
+          <CardTitle>New Follow-up</CardTitle>
+        </CardHeader>
+        <CardContent>
+          <form.AppForm>
+            <form.Form id='lead-followup-form' className='grid gap-4 md:grid-cols-2'>
+              <FormTextField name='followupDate' label='Follow-up Date' placeholder='YYYY-MM-DD' />
+              <FormTextField
+                name='nextFollowupDate'
+                label='Next Follow-up Date'
+                placeholder='YYYY-MM-DD'
+              />
+              <FormSelectField
+                name='followupStatus'
+                label='Follow-up Status'
+                options={detail.referenceData.followupStatuses.map((item) => ({
+                  value: item.id,
+                  label: item.label
+                }))}
+              />
+              <div />
+              <FormTextareaField name='note' label='Note' className='md:col-span-2' />
+              <div className='md:col-span-2'>
+                <Button type='submit' form='lead-followup-form' isLoading={mutation.isPending}>
+                  Save Follow-up
+                </Button>
+              </div>
+            </form.Form>
+          </form.AppForm>
+        </CardContent>
+      </Card>
+
+      <Card>
+        <CardHeader>
+          <CardTitle>History</CardTitle>
+        </CardHeader>
+        <CardContent className='space-y-3'>
+          {detail.followups.length === 0 ? (
+            <div className='text-muted-foreground text-sm'>No follow-up history yet.</div>
+          ) : (
+            detail.followups.map((followup) => (
+              <div key={followup.id} className='border-border rounded-md border p-3'>
+                <div className='flex items-center justify-between gap-3'>
+                  <div className='font-medium'>{followup.followupStatusLabel ?? followup.followupStatus}</div>
+                  <div className='text-muted-foreground text-xs'>
+                    {new Date(followup.followupDate).toLocaleDateString()}
+                  </div>
+                </div>
+                {followup.note ? <div className='mt-2 text-sm'>{followup.note}</div> : null}
+                <div className='text-muted-foreground mt-2 text-xs'>
+                  {followup.createdByName ?? followup.createdBy}
+                </div>
+              </div>
+            ))
+          )}
+        </CardContent>
+      </Card>
+    </div>
+  );
+}
diff --git a/src/features/crm/leads/components/lead-form.tsx b/src/features/crm/leads/components/lead-form.tsx
new file mode 100644
index 0000000..1afde33
--- /dev/null
+++ b/src/features/crm/leads/components/lead-form.tsx
@@ -0,0 +1,323 @@
+'use client';
+
+import * as React from 'react';
+import { useEffect, useMemo, useState } from 'react';
+import { useMutation } from '@tanstack/react-query';
+import { toast } from 'sonner';
+import { Icons } from '@/components/icons';
+import { Button } from '@/components/ui/button';
+import { Select, SelectContent, SelectItem, SelectTrigger, SelectValue } from '@/components/ui/select';
+import {
+  Sheet,
+  SheetContent,
+  SheetDescription,
+  SheetFooter,
+  SheetHeader,
+  SheetTitle
+} from '@/components/ui/sheet';
+import { useAppForm, useFormFields } from '@/components/ui/tanstack-form';
+import { createLeadMutation, updateLeadMutation } from '../api/mutations';
+import type { LeadReferenceData, LeadSummary } from '../api/types';
+import { leadSchema } from '../schemas/lead.schema';
+
+type LeadFormValues = {
+  branchId: string | null;
+  customerId: string | null;
+  contactId: string | null;
+  description: string | null;
+  projectName: string | null;
+  projectLocation: string | null;
+  productType: string | null;
+  priority: string | null;
+  estimatedValue: number | null;
+  awarenessId: string | null;
+  status: string;
+  followupStatus: string | null;
+  lostReason: string | null;
+  outcome: 'open' | 'won' | 'lost';
+  ownerMarketingUserId: string | null;
+};
+
+function toDefaultValues(lead: LeadSummary | undefined, referenceData: LeadReferenceData): LeadFormValues {
+  return {
+    branchId: lead?.branchId ?? referenceData.branches[0]?.id ?? null,
+    customerId: lead?.customerId ?? null,
+    contactId: lead?.contactId ?? null,
+    description: lead?.description ?? null,
+    projectName: lead?.projectName ?? null,
+    projectLocation: lead?.projectLocation ?? null,
+    productType: lead?.productType ?? referenceData.productTypes[0]?.id ?? null,
+    priority: lead?.priority ?? referenceData.priorities[0]?.id ?? null,
+    estimatedValue: lead?.estimatedValue ?? null,
+    awarenessId: lead?.awarenessId ?? referenceData.awarenesses[0]?.id ?? null,
+    status: lead?.status ?? referenceData.statuses[0]?.id ?? '',
+    followupStatus: lead?.followupStatus ?? null,
+    lostReason: lead?.lostReason ?? null,
+    outcome: (lead?.outcome as 'open' | 'won' | 'lost' | undefined) ?? 'open',
+    ownerMarketingUserId: lead?.ownerMarketingUserId ?? null
+  };
+}
+
+export function LeadForm({
+  open,
+  onOpenChange,
+  referenceData,
+  lead
+}: {
+  open: boolean;
+  onOpenChange: (open: boolean) => void;
+  referenceData: LeadReferenceData;
+  lead?: LeadSummary;
+}) {
+  const isEdit = Boolean(lead);
+  const defaultValues = useMemo(() => toDefaultValues(lead, referenceData), [lead, referenceData]);
+  const [selectedCustomerId, setSelectedCustomerId] = useState(defaultValues.customerId ?? '');
+  const { FormTextField, FormTextareaField, FormSelectField, FormCurrencyField } =
+    useFormFields<LeadFormValues>();
+
+  const createMutation = useMutation({
+    ...createLeadMutation,
+    onSuccess: () => {
+      toast.success('สร้างลีดสำเร็จ');
+      onOpenChange(false);
+    },
+    onError: (error) => {
+      toast.error(error instanceof Error ? error.message : 'ไม่สามารถสร้างลีดได้');
+    }
+  });
+
+  const updateMutation = useMutation({
+    ...updateLeadMutation,
+    onSuccess: () => {
+      toast.success('อัปเดตลีดสำเร็จ');
+      onOpenChange(false);
+    },
+    onError: (error) => {
+      toast.error(error instanceof Error ? error.message : 'ไม่สามารถอัปเดตลีดได้');
+    }
+  });
+
+  const contactsForCustomer = referenceData.contacts.filter(
+    (contact) => contact.customerId === selectedCustomerId
+  );
+
+  const form = useAppForm({
+    defaultValues,
+    onSubmit: async ({ value }) => {
+      const payload = {
+        ...value,
+        branchId: value.branchId || null,
+        customerId: value.customerId || null,
+        contactId: value.contactId || null,
+        description: value.description || null,
+        projectName: value.projectName || null,
+        projectLocation: value.projectLocation || null,
+        productType: value.productType || null,
+        priority: value.priority || null,
+        estimatedValue: value.estimatedValue ?? null,
+        awarenessId: value.awarenessId || null,
+        followupStatus: value.followupStatus || null,
+        lostReason: value.lostReason || null,
+        ownerMarketingUserId: value.ownerMarketingUserId || null
+      };
+
+      if (isEdit && lead) {
+        await updateMutation.mutateAsync({ id: lead.id, values: payload });
+        return;
+      }
+
+      await createMutation.mutateAsync(payload);
+    }
+  });
+
+  useEffect(() => {
+    if (!open) return;
+
+    form.reset(defaultValues);
+    setSelectedCustomerId(defaultValues.customerId ?? '');
+  }, [defaultValues, form, open]);
+
+  return (
+    <Sheet open={open} onOpenChange={onOpenChange}>
+      <SheetContent className='flex w-full flex-col sm:max-w-3xl'>
+        <SheetHeader>
+          <SheetTitle>{isEdit ? 'แก้ไขลีด' : 'สร้างลีด'}</SheetTitle>
+          <SheetDescription>บันทึกข้อมูลลีดของฝ่ายการตลาดก่อนส่งต่อให้ฝ่ายขาย</SheetDescription>
+        </SheetHeader>
+
+        <div className='flex-1 overflow-auto'>
+          <form.AppForm>
+            <form.Form id='lead-form' className='grid gap-4 md:grid-cols-2'>
+              <form.AppField
+                name='customerId'
+                children={(field) => (
+                  <field.FieldSet>
+                    <field.Field>
+                      <field.FieldLabel>ลูกค้า</field.FieldLabel>
+                      <Select
+                        value={field.state.value ?? ''}
+                        onValueChange={(nextValue) => {
+                          field.handleChange(nextValue === '__none__' ? null : nextValue);
+                          field.handleBlur();
+                          setSelectedCustomerId(nextValue === '__none__' ? '' : nextValue);
+                          form.setFieldValue('contactId', null);
+                        }}
+                      >
+                        <SelectTrigger aria-label='ลูกค้า'>
+                          <SelectValue placeholder='เลือกลูกค้า' />
+                        </SelectTrigger>
+                        <SelectContent>
+                          <SelectItem value='__none__'>ไม่เลือก</SelectItem>
+                          {referenceData.customers.map((customer) => (
+                            <SelectItem key={customer.id} value={customer.id}>
+                              {customer.name} ({customer.code})
+                            </SelectItem>
+                          ))}
+                        </SelectContent>
+                      </Select>
+                    </field.Field>
+                    <field.FieldError />
+                  </field.FieldSet>
+                )}
+              />
+
+              <form.AppField
+                name='contactId'
+                children={(field) => (
+                  <field.FieldSet>
+                    <field.Field>
+                      <field.FieldLabel>ผู้ติดต่อ</field.FieldLabel>
+                      <Select
+                        value={field.state.value ?? '__none__'}
+                        onValueChange={(nextValue) => {
+                          field.handleChange(nextValue === '__none__' ? null : nextValue);
+                          field.handleBlur();
+                        }}
+                      >
+                        <SelectTrigger aria-label='ผู้ติดต่อ'>
+                          <SelectValue placeholder='เลือกผู้ติดต่อ' />
+                        </SelectTrigger>
+                        <SelectContent>
+                          <SelectItem value='__none__'>ไม่เลือก</SelectItem>
+                          {contactsForCustomer.map((contact) => (
+                            <SelectItem key={contact.id} value={contact.id}>
+                              {contact.name}
+                              {contact.isPrimary ? ' (หลัก)' : ''}
+                            </SelectItem>
+                          ))}
+                        </SelectContent>
+                      </Select>
+                    </field.Field>
+                    <field.FieldError />
+                  </field.FieldSet>
+                )}
+              />
+
+              <FormTextField name='projectName' label='Project Name' />
+              <FormTextField name='projectLocation' label='Project Location' />
+              <FormTextareaField name='description' label='Description' className='md:col-span-2' />
+
+              <FormSelectField
+                name='branchId'
+                label='สาขา'
+                options={referenceData.branches.map((branch) => ({
+                  value: branch.id,
+                  label: branch.name
+                }))}
+              />
+              <FormSelectField
+                name='productType'
+                label='Product Type'
+                options={referenceData.productTypes.map((item) => ({
+                  value: item.id,
+                  label: item.label
+                }))}
+              />
+              <FormSelectField
+                name='priority'
+                label='Priority'
+                options={referenceData.priorities.map((item) => ({
+                  value: item.id,
+                  label: item.label
+                }))}
+              />
+              <FormCurrencyField name='estimatedValue' label='Estimated Value' currencyLabel='THB' />
+              <FormSelectField
+                name='awarenessId'
+                label='Awareness'
+                options={referenceData.awarenesses.map((item) => ({
+                  value: item.id,
+                  label: item.label
+                }))}
+              />
+              <FormSelectField
+                name='status'
+                label='Status'
+                options={referenceData.statuses.map((item) => ({
+                  value: item.id,
+                  label: item.label
+                }))}
+              />
+              <FormSelectField
+                name='followupStatus'
+                label='Follow-up Status'
+                options={referenceData.followupStatuses.map((item) => ({
+                  value: item.id,
+                  label: item.label
+                }))}
+              />
+              <FormSelectField
+                name='lostReason'
+                label='Lost Reason'
+                options={referenceData.lostReasons.map((item) => ({
+                  value: item.id,
+                  label: item.label
+                }))}
+              />
+              <FormSelectField
+                name='ownerMarketingUserId'
+                label='Marketing Owner'
+                options={referenceData.assignableUsers.map((user) => ({
+                  value: user.id,
+                  label: user.name
+                }))}
+              />
+            </form.Form>
+          </form.AppForm>
+        </div>
+
+        <SheetFooter>
+          <Button
+            variant='outline'
+            onClick={() => onOpenChange(false)}
+            disabled={createMutation.isPending || updateMutation.isPending}
+          >
+            ยกเลิก
+          </Button>
+          <Button
+            type='submit'
+            form='lead-form'
+            isLoading={createMutation.isPending || updateMutation.isPending}
+          >
+            <Icons.add className='mr-2 h-4 w-4' />
+            {isEdit ? 'อัปเดตลีด' : 'สร้างลีด'}
+          </Button>
+        </SheetFooter>
+      </SheetContent>
+    </Sheet>
+  );
+}
+
+export function LeadFormTrigger({ referenceData }: { referenceData: LeadReferenceData }) {
+  const [open, setOpen] = React.useState(false);
+
+  return (
+    <>
+      <Button onClick={() => setOpen(true)}>
+        <Icons.add className='mr-2 h-4 w-4' />
+        เพิ่มลีด
+      </Button>
+      <LeadForm open={open} onOpenChange={setOpen} referenceData={referenceData} />
+    </>
+  );
+}
diff --git a/src/features/crm/leads/components/lead-list.tsx b/src/features/crm/leads/components/lead-list.tsx
new file mode 100644
index 0000000..c9931d0
--- /dev/null
+++ b/src/features/crm/leads/components/lead-list.tsx
@@ -0,0 +1,48 @@
+import { HydrationBoundary, dehydrate } from '@tanstack/react-query';
+import { getQueryClient } from '@/lib/query-client';
+import { searchParamsCache } from '@/lib/searchparams';
+import type { LeadReferenceData } from '../api/types';
+import { leadsQueryOptions } from '../api/queries';
+import { LeadsTable } from './leads-table';
+
+export function LeadList({
+  referenceData,
+  canUpdate,
+  canDelete,
+  canAssign
+}: {
+  referenceData: LeadReferenceData;
+  canUpdate: boolean;
+  canDelete: boolean;
+  canAssign: boolean;
+}) {
+  const page = searchParamsCache.get('page');
+  const limit = searchParamsCache.get('perPage');
+  const search = searchParamsCache.get('name');
+  const status = searchParamsCache.get('status');
+  const branch = searchParamsCache.get('branch');
+  const customer = searchParamsCache.get('customer');
+  const sort = searchParamsCache.get('sort');
+  const filters = {
+    page,
+    limit,
+    ...(search && { search }),
+    ...(status && { status }),
+    ...(branch && { branchId: branch }),
+    ...(customer && { customerId: customer }),
+    ...(sort && { sort })
+  };
+  const queryClient = getQueryClient();
+  void queryClient.prefetchQuery(leadsQueryOptions(filters));
+
+  return (
+    <HydrationBoundary state={dehydrate(queryClient)}>
+      <LeadsTable
+        referenceData={referenceData}
+        canUpdate={canUpdate}
+        canDelete={canDelete}
+        canAssign={canAssign}
+      />
+    </HydrationBoundary>
+  );
+}
diff --git a/src/features/crm/leads/components/leads-table.tsx b/src/features/crm/leads/components/leads-table.tsx
new file mode 100644
index 0000000..f486f6f
--- /dev/null
+++ b/src/features/crm/leads/components/leads-table.tsx
@@ -0,0 +1,68 @@
+'use client';
+
+import { useMemo } from 'react';
+import { parseAsInteger, parseAsString, useQueryStates } from 'nuqs';
+import { useSuspenseQuery } from '@tanstack/react-query';
+import { DataTable } from '@/components/ui/table/data-table';
+import { DataTableToolbar } from '@/components/ui/table/data-table-toolbar';
+import { useDataTable } from '@/hooks/use-data-table';
+import { getSortingStateParser } from '@/lib/parsers';
+import type { LeadReferenceData } from '../api/types';
+import { leadsQueryOptions } from '../api/queries';
+import { getLeadColumns } from './lead-columns';
+
+export function LeadsTable({
+  referenceData,
+  canUpdate,
+  canDelete,
+  canAssign
+}: {
+  referenceData: LeadReferenceData;
+  canUpdate: boolean;
+  canDelete: boolean;
+  canAssign: boolean;
+}) {
+  const columns = useMemo(
+    () => getLeadColumns({ referenceData, canUpdate, canDelete, canAssign }),
+    [referenceData, canUpdate, canDelete, canAssign]
+  );
+  const columnIds = columns.map((column) => column.id).filter(Boolean) as string[];
+
+  const [params] = useQueryStates({
+    page: parseAsInteger.withDefault(1),
+    perPage: parseAsInteger.withDefault(10),
+    name: parseAsString,
+    status: parseAsString,
+    branchId: parseAsString,
+    customerId: parseAsString,
+    sort: getSortingStateParser(columnIds).withDefault([])
+  });
+
+  const filters = {
+    page: params.page,
+    limit: params.perPage,
+    ...(params.name && { search: params.name }),
+    ...(params.status && { status: params.status }),
+    ...(params.branchId && { branchId: params.branchId }),
+    ...(params.customerId && { customerId: params.customerId }),
+    ...(params.sort.length > 0 && { sort: JSON.stringify(params.sort) })
+  };
+
+  const { data } = useSuspenseQuery(leadsQueryOptions(filters));
+  const pageCount = Math.max(1, Math.ceil((data.totalItems || 0) / params.perPage));
+
+  const { table } = useDataTable({
+    data: data.items,
+    columns,
+    pageCount,
+    shallow: true,
+    debounceMs: 500,
+    clearOnDefault: true
+  });
+
+  return (
+    <DataTable table={table}>
+      <DataTableToolbar table={table} />
+    </DataTable>
+  );
+}
diff --git a/src/features/crm/leads/server/assignment.service.ts b/src/features/crm/leads/server/assignment.service.ts
index 4a7ec06..d187b08 100644
--- a/src/features/crm/leads/server/assignment.service.ts
+++ b/src/features/crm/leads/server/assignment.service.ts
@@ -243,7 +243,8 @@ export async function assignLead(
     return {
       leadId: input.leadId,
       enquiryId: existingEnquiry.id,
-      enquiryCode: existingEnquiry.code
+      enquiryCode: existingEnquiry.code,
+      reusedExistingEnquiry: true
     };
   }
 
@@ -295,6 +296,7 @@ export async function assignLead(
   return {
     leadId: input.leadId,
     enquiryId: createdEnquiry.id,
-    enquiryCode: createdEnquiry.code
+    enquiryCode: createdEnquiry.code,
+    reusedExistingEnquiry: false
   };
 }
diff --git a/src/features/crm/leads/server/service.ts b/src/features/crm/leads/server/service.ts
index df75737..91656d7 100644
--- a/src/features/crm/leads/server/service.ts
+++ b/src/features/crm/leads/server/service.ts
@@ -23,7 +23,7 @@ import { db } from '@/lib/db';
 import { AuthError } from '@/lib/auth/session';
 import { getUserBranches, validateBranchAccess } from '@/features/foundation/branch-scope/service';
 import { generateNextDocumentCode } from '@/features/foundation/document-sequence/service';
-import { auditAction } from '@/features/foundation/audit-log/service';
+import { auditAction, listAuditLogs } from '@/features/foundation/audit-log/service';
 import { getActiveOptionsByCategory } from '@/features/foundation/master-options/service';
 import {
   buildCrmSecurityContext,
@@ -34,9 +34,14 @@ import {
 import type {
   CreateLeadFollowupInput,
   CreateLeadInput,
+  LeadActivityRecord,
+  LeadAssignableUserLookup,
   LeadBranchOption,
+  LeadContactLookup,
+  LeadCustomerLookup,
   LeadDetail,
   LeadFollowupSummary,
+  LeadLinkedEnquirySummary,
   LeadListFilters,
   LeadListResponse,
   LeadOption,
@@ -66,6 +71,7 @@ type LeadLookupMaps = {
   productTypeLabels: Map<string, string>;
   priorityLabels: Map<string, string>;
   customerNames: Map<string, string>;
+  customerOwnerIds: Map<string, string | null>;
   contactNames: Map<string, string>;
   userNames: Map<string, string>;
 };
@@ -92,6 +98,170 @@ function mapOption(
   };
 }
 
+async function listAssignableLeadUsers(organizationId: string): Promise<LeadAssignableUserLookup[]> {
+  const rows = await db
+    .select({
+      userId: memberships.userId,
+      membershipRole: memberships.role,
+      businessRole: memberships.businessRole,
+      name: users.name
+    })
+    .from(memberships)
+    .innerJoin(users, eq(memberships.userId, users.id))
+    .where(eq(memberships.organizationId, organizationId))
+    .orderBy(asc(users.name));
+
+  const uniqueRows = [...new Map(rows.map((row) => [row.userId, row])).values()];
+
+  return uniqueRows
+    .filter(
+      (row) =>
+        row.membershipRole === 'admin' ||
+        ['sales_manager', 'sales', 'sales_support'].includes(row.businessRole)
+    )
+    .map((row) => ({
+      id: row.userId,
+      name: row.name,
+      membershipRole: row.membershipRole === 'admin' ? 'admin' : 'user',
+      businessRole: row.businessRole
+    }));
+}
+
+async function listLeadCustomers(organizationId: string): Promise<LeadCustomerLookup[]> {
+  const rows = await db
+    .select({
+      id: crmCustomers.id,
+      code: crmCustomers.code,
+      name: crmCustomers.name,
+      branchId: crmCustomers.branchId,
+      ownerUserId: crmCustomers.ownerUserId
+    })
+    .from(crmCustomers)
+    .where(and(eq(crmCustomers.organizationId, organizationId), isNull(crmCustomers.deletedAt)))
+    .orderBy(asc(crmCustomers.name));
+
+  const ownerIds = [
+    ...new Set(rows.map((row) => row.ownerUserId).filter((value): value is string => Boolean(value)))
+  ];
+  const owners = ownerIds.length
+    ? await db
+        .select({ id: users.id, name: users.name })
+        .from(users)
+        .where(inArray(users.id, ownerIds))
+    : [];
+  const ownerMap = new Map(owners.map((row) => [row.id, row.name]));
+
+  return rows.map((row) => ({
+    id: row.id,
+    code: row.code,
+    name: row.name,
+    branchId: row.branchId ?? null,
+    ownerUserId: row.ownerUserId ?? null,
+    ownerName: row.ownerUserId ? (ownerMap.get(row.ownerUserId) ?? null) : null
+  }));
+}
+
+async function listLeadContacts(organizationId: string): Promise<LeadContactLookup[]> {
+  const rows = await db
+    .select({
+      id: crmCustomerContacts.id,
+      customerId: crmCustomerContacts.customerId,
+      name: crmCustomerContacts.name,
+      email: crmCustomerContacts.email,
+      mobile: crmCustomerContacts.mobile,
+      isPrimary: crmCustomerContacts.isPrimary
+    })
+    .from(crmCustomerContacts)
+    .where(
+      and(eq(crmCustomerContacts.organizationId, organizationId), isNull(crmCustomerContacts.deletedAt))
+    )
+    .orderBy(desc(crmCustomerContacts.isPrimary), asc(crmCustomerContacts.name));
+
+  return rows.map((row) => ({
+    id: row.id,
+    customerId: row.customerId,
+    name: row.name,
+    email: row.email ?? null,
+    mobile: row.mobile ?? null,
+    isPrimary: row.isPrimary
+  }));
+}
+
+async function listLinkedEnquiries(
+  leadId: string,
+  organizationId: string
+): Promise<LeadLinkedEnquirySummary[]> {
+  const rows = await db
+    .select({
+      id: crmEnquiries.id,
+      code: crmEnquiries.code,
+      title: crmEnquiries.title,
+      status: crmEnquiries.status,
+      assignedToUserId: crmEnquiries.assignedToUserId,
+      updatedAt: crmEnquiries.updatedAt
+    })
+    .from(crmEnquiries)
+    .where(
+      and(
+        eq(crmEnquiries.organizationId, organizationId),
+        eq(crmEnquiries.leadId, leadId),
+        isNull(crmEnquiries.deletedAt)
+      )
+    )
+    .orderBy(desc(crmEnquiries.updatedAt));
+
+  const assigneeIds = [
+    ...new Set(rows.map((row) => row.assignedToUserId).filter((value): value is string => Boolean(value)))
+  ];
+  const assigneeRows = assigneeIds.length
+    ? await db
+        .select({ id: users.id, name: users.name })
+        .from(users)
+        .where(inArray(users.id, assigneeIds))
+    : [];
+  const assigneeMap = new Map(assigneeRows.map((row) => [row.id, row.name]));
+
+  return rows.map((row) => ({
+    id: row.id,
+    code: row.code,
+    title: row.title,
+    status: row.status,
+    assignedToUserId: row.assignedToUserId ?? null,
+    assignedToName: row.assignedToUserId ? (assigneeMap.get(row.assignedToUserId) ?? null) : null,
+    updatedAt: row.updatedAt.toISOString()
+  }));
+}
+
+async function listLeadActivity(
+  leadId: string,
+  organizationId: string
+): Promise<LeadActivityRecord[]> {
+  const auditLogs = await listAuditLogs({
+    organizationId,
+    entityType: 'crm_lead',
+    entityId: leadId,
+    limit: 25
+  });
+  const userIds = [...new Set(auditLogs.map((log) => log.userId))];
+  const actorRows = userIds.length
+    ? await db
+        .select({ id: users.id, name: users.name })
+        .from(users)
+        .where(inArray(users.id, userIds))
+    : [];
+  const actorMap = new Map(actorRows.map((row) => [row.id, row.name]));
+
+  return auditLogs.map((log) => ({
+    id: log.id,
+    action: log.action,
+    entityType: log.entityType,
+    entityId: log.entityId,
+    createdAt: log.createdAt,
+    userId: log.userId,
+    actorName: actorMap.get(log.userId) ?? null
+  }));
+}
+
 function mapBranch(
   branch: Awaited<ReturnType<typeof getUserBranches>>[number]
 ): LeadBranchOption {
@@ -150,6 +320,11 @@ function mapLeadSummary(row: LeadRow, lookups: LeadLookupMaps): LeadSummary {
     assignedSalesOwnerName: row.assignedSalesOwnerId
       ? (lookups.userNames.get(row.assignedSalesOwnerId) ?? null)
       : null,
+    suggestedSalesOwnerId: row.customerId ? (lookups.customerOwnerIds.get(row.customerId) ?? null) : null,
+    suggestedSalesOwnerName:
+      row.customerId && lookups.customerOwnerIds.get(row.customerId)
+        ? (lookups.userNames.get(lookups.customerOwnerIds.get(row.customerId) ?? '') ?? null)
+        : null,
     assignedAt: toIsoDateTime(row.assignedAt),
     assignedBy: row.assignedBy ?? null,
     assignedByName: row.assignedBy ? (lookups.userNames.get(row.assignedBy) ?? null) : null,
@@ -170,7 +345,9 @@ function mapLeadDetail(
   return {
     ...mapLeadSummary(row, lookups),
     suggestedSalesOwnerId,
-    relatedEnquiryCount
+    relatedEnquiryCount,
+    linkedEnquiries: [],
+    activity: []
   };
 }
 
@@ -383,10 +560,10 @@ async function buildLookupMaps(organizationId: string, rows: LeadRow[]): Promise
     )
   ];
 
-  const [customerRows, contactRows, userRows] = await Promise.all([
+  const [customerRows, contactRows] = await Promise.all([
     customerIds.length
       ? db
-          .select({ id: crmCustomers.id, name: crmCustomers.name })
+          .select({ id: crmCustomers.id, name: crmCustomers.name, ownerUserId: crmCustomers.ownerUserId })
           .from(crmCustomers)
           .where(inArray(crmCustomers.id, customerIds))
       : Promise.resolve([]),
@@ -396,13 +573,22 @@ async function buildLookupMaps(organizationId: string, rows: LeadRow[]): Promise
           .from(crmCustomerContacts)
           .where(inArray(crmCustomerContacts.id, contactIds))
       : Promise.resolve([]),
-    userIds.length
-      ? db
-          .select({ id: users.id, name: users.name })
-          .from(users)
-          .where(inArray(users.id, userIds))
-      : Promise.resolve([])
   ]);
+  const resolvedUserIds = [
+    ...new Set(
+      userIds.concat(
+        customerRows
+          .map((item) => item.ownerUserId)
+          .filter((value): value is string => Boolean(value))
+      )
+    )
+  ];
+  const userRows = resolvedUserIds.length
+    ? await db
+        .select({ id: users.id, name: users.name })
+        .from(users)
+        .where(inArray(users.id, resolvedUserIds))
+    : [];
 
   return {
     awarenessLabels: new Map(awarenesses.map((item) => [item.id, item.label])),
@@ -412,6 +598,7 @@ async function buildLookupMaps(organizationId: string, rows: LeadRow[]): Promise
     productTypeLabels: new Map(productTypes.map((item) => [item.id, item.label])),
     priorityLabels: new Map(priorities.map((item) => [item.id, item.label])),
     customerNames: new Map(customerRows.map((item) => [item.id, item.name])),
+    customerOwnerIds: new Map(customerRows.map((item) => [item.id, item.ownerUserId ?? null])),
     contactNames: new Map(contactRows.map((item) => [item.id, item.name])),
     userNames: new Map(userRows.map((item) => [item.id, item.name]))
   };
@@ -486,7 +673,18 @@ async function validateLeadPayload(
 }
 
 export async function getLeadReferenceData(organizationId: string): Promise<LeadReferenceData> {
-  const [awarenesses, statuses, followupStatuses, lostReasons, productTypes, priorities, branches] =
+  const [
+    awarenesses,
+    statuses,
+    followupStatuses,
+    lostReasons,
+    productTypes,
+    priorities,
+    branches,
+    customers,
+    contacts,
+    assignableUsers
+  ] =
     await Promise.all([
       getActiveOptionsByCategory(LEAD_OPTION_CATEGORIES.awareness, { organizationId }),
       getActiveOptionsByCategory(LEAD_OPTION_CATEGORIES.status, { organizationId }),
@@ -494,7 +692,10 @@ export async function getLeadReferenceData(organizationId: string): Promise<Lead
       getActiveOptionsByCategory(LEAD_OPTION_CATEGORIES.lostReason, { organizationId }),
       getActiveOptionsByCategory(LEAD_OPTION_CATEGORIES.productType, { organizationId }),
       getActiveOptionsByCategory(LEAD_OPTION_CATEGORIES.priority, { organizationId }),
-      getUserBranches()
+      getUserBranches(),
+      listLeadCustomers(organizationId),
+      listLeadContacts(organizationId),
+      listAssignableLeadUsers(organizationId)
     ]);
 
   return {
@@ -504,7 +705,10 @@ export async function getLeadReferenceData(organizationId: string): Promise<Lead
     lostReasons: lostReasons.map(mapOption),
     productTypes: productTypes.map(mapOption),
     priorities: priorities.map(mapOption),
-    branches: branches.map(mapBranch)
+    branches: branches.map(mapBranch),
+    customers,
+    contacts,
+    assignableUsers
   };
 }
 
@@ -512,7 +716,7 @@ export async function listLeads(
   organizationId: string,
   filters: LeadListFilters = {},
   accessContext?: LeadAccessContext
-): Promise<LeadListResponse> {
+): Promise<{ items: LeadSummary[]; totalItems: number }> {
   const page = filters.page ?? 1;
   const limit = filters.limit ?? 10;
   const offset = (page - 1) * limit;
@@ -562,7 +766,7 @@ export async function getLeadById(
   accessContext?: LeadAccessContext
 ): Promise<LeadDetail> {
   const lead = await assertLeadBelongsToOrganization(id, organizationId, accessContext);
-  const [lookups, relatedEnquiryResult, customer] = await Promise.all([
+  const [lookups, relatedEnquiryResult, customer, linkedEnquiries, activity] = await Promise.all([
     buildLookupMaps(organizationId, [lead]),
     db
       .select({ value: count() })
@@ -574,15 +778,22 @@ export async function getLeadById(
           isNull(crmEnquiries.deletedAt)
         )
       ),
-    lead.customerId ? assertCustomerBelongsToOrganization(lead.customerId, organizationId) : Promise.resolve(null)
+    lead.customerId ? assertCustomerBelongsToOrganization(lead.customerId, organizationId) : Promise.resolve(null),
+    listLinkedEnquiries(id, organizationId),
+    listLeadActivity(id, organizationId)
   ]);
-
-  return mapLeadDetail(
+  const detail = mapLeadDetail(
     lead,
     lookups,
     customer?.ownerUserId ?? null,
     relatedEnquiryResult[0]?.value ?? 0
   );
+
+  return {
+    ...detail,
+    linkedEnquiries,
+    activity
+  };
 }
 
 export async function createLead(
@@ -713,7 +924,11 @@ export async function deleteLead(
 
     const lookups = await buildLookupMaps(organizationId, deleted ? [deleted] : []);
 
-    return mapLeadDetail(deleted!, lookups, null, 0);
+    return {
+      ...mapLeadDetail(deleted!, lookups, null, 0),
+      linkedEnquiries: [],
+      activity: []
+    };
   });
 }
 
diff --git a/src/features/crm/leads/types.ts b/src/features/crm/leads/types.ts
index 2a7390f..953cda4 100644
--- a/src/features/crm/leads/types.ts
+++ b/src/features/crm/leads/types.ts
@@ -12,6 +12,51 @@ export interface LeadBranchOption {
   value: string | null;
 }
 
+export interface LeadAssignableUserLookup {
+  id: string;
+  name: string;
+  membershipRole: 'admin' | 'user';
+  businessRole: string;
+}
+
+export interface LeadCustomerLookup {
+  id: string;
+  code: string;
+  name: string;
+  branchId: string | null;
+  ownerUserId: string | null;
+  ownerName: string | null;
+}
+
+export interface LeadContactLookup {
+  id: string;
+  customerId: string;
+  name: string;
+  email: string | null;
+  mobile: string | null;
+  isPrimary: boolean;
+}
+
+export interface LeadLinkedEnquirySummary {
+  id: string;
+  code: string;
+  title: string;
+  status: string;
+  assignedToUserId: string | null;
+  assignedToName: string | null;
+  updatedAt: string;
+}
+
+export interface LeadActivityRecord {
+  id: string;
+  action: string;
+  entityType: string;
+  entityId: string;
+  createdAt: string;
+  userId: string;
+  actorName: string | null;
+}
+
 export interface LeadReferenceData {
   awarenesses: LeadOption[];
   statuses: LeadOption[];
@@ -20,6 +65,9 @@ export interface LeadReferenceData {
   productTypes: LeadOption[];
   priorities: LeadOption[];
   branches: LeadBranchOption[];
+  customers: LeadCustomerLookup[];
+  contacts: LeadContactLookup[];
+  assignableUsers: LeadAssignableUserLookup[];
 }
 
 export interface CreateLeadInput {
@@ -113,6 +161,8 @@ export interface LeadSummary {
   ownerMarketingName: string | null;
   assignedSalesOwnerId: string | null;
   assignedSalesOwnerName: string | null;
+  suggestedSalesOwnerId: string | null;
+  suggestedSalesOwnerName: string | null;
   assignedAt: string | null;
   assignedBy: string | null;
   assignedByName: string | null;
@@ -124,13 +174,9 @@ export interface LeadSummary {
 }
 
 export interface LeadDetail extends LeadSummary {
-  suggestedSalesOwnerId: string | null;
   relatedEnquiryCount: number;
-}
-
-export interface LeadListResponse {
-  items: LeadSummary[];
-  totalItems: number;
+  linkedEnquiries: LeadLinkedEnquirySummary[];
+  activity: LeadActivityRecord[];
 }
 
 export interface LeadFollowupSummary {
@@ -150,4 +196,32 @@ export interface AssignLeadResult {
   leadId: string;
   enquiryId: string;
   enquiryCode: string;
+  reusedExistingEnquiry: boolean;
+}
+
+export interface LeadListResponse {
+  success: boolean;
+  time: string;
+  message: string;
+  totalItems: number;
+  offset: number;
+  limit: number;
+  items: LeadSummary[];
+  referenceData: LeadReferenceData;
+}
+
+export interface LeadDetailResponse {
+  success: boolean;
+  time: string;
+  message: string;
+  lead: LeadDetail;
+  followups: LeadFollowupSummary[];
+  referenceData: LeadReferenceData;
+}
+
+export interface LeadMutationSuccessResponse {
+  success: boolean;
+  message: string;
+  lead?: LeadDetail;
+  followup?: LeadFollowupSummary;
 }