diff --git a/services/platform-service/src/lib/cosmos-init.ts b/services/platform-service/src/lib/cosmos-init.ts
index e2276ac5..5a71f777 100644
--- a/services/platform-service/src/lib/cosmos-init.ts
+++ b/services/platform-service/src/lib/cosmos-init.ts
@@ -41,6 +41,8 @@ const CONTAINER_DEFS: Record<string, ContainerConfig> = {
   email_verifications: { partitionKeyPath: '/productId', defaultTtl: 7 * 86400 },
   // SmartAuth — OAuth provider linking
   auth_providers: { partitionKeyPath: '/userId' },
+  // SmartAuth — Enterprise IdP configs
+  auth_enterprise_idps: { partitionKeyPath: '/orgId' },
   // SmartAuth — TOTP MFA secrets + recovery codes
   auth_mfa: { partitionKeyPath: '/userId' },
   // SmartAuth — MFA enforcement policies (per product)
@@ -63,6 +65,10 @@ const CONTAINER_DEFS: Record<string, ContainerConfig> = {
   // Generic orchestration runs
   agent_runs: { partitionKeyPath: '/productId', defaultTtl: 30 * 86400 },
   agent_run_steps: { partitionKeyPath: '/pk', defaultTtl: 30 * 86400 },
+  // Canonical tenant model
+  organizations: { partitionKeyPath: '/productId' },
+  workspaces: { partitionKeyPath: '/orgId' },
+  org_memberships: { partitionKeyPath: '/orgId' },
   // Telemetry (client diagnostics — see docs/WINDSURF/CLIENT_TELEMETRY_DESIGN.md)
   telemetry_events: { partitionKeyPath: '/pk', defaultTtl: 30 * 86400 },
   telemetry_error_clusters: { partitionKeyPath: '/pk', defaultTtl: 90 * 86400 },
diff --git a/services/platform-service/src/modules/orgs/repository.test.ts b/services/platform-service/src/modules/orgs/repository.test.ts
new file mode 100644
index 00000000..a3471519
--- /dev/null
+++ b/services/platform-service/src/modules/orgs/repository.test.ts
@@ -0,0 +1,59 @@
+import { afterEach, beforeEach, describe, expect, it } from 'vitest';
+import { MemoryDatastoreProvider } from '@bytelyst/datastore';
+import { _resetDatastoreProvider, setProvider } from '../../lib/datastore.js';
+import * as repo from './repository.js';
+
+describe('orgs repository', () => {
+  beforeEach(() => {
+    setProvider(new MemoryDatastoreProvider());
+  });
+
+  afterEach(() => {
+    _resetDatastoreProvider();
+  });
+
+  it('creates orgs, workspaces, and memberships', async () => {
+    await repo.createOrganization({
+      id: 'org_1',
+      productId: 'lysnrai',
+      name: 'Acme',
+      slug: 'acme',
+      status: 'active',
+      ownerUserId: 'user_1',
+      createdAt: '2026-03-15T00:00:00.000Z',
+      updatedAt: '2026-03-15T00:00:00.000Z',
+    });
+
+    await repo.createWorkspace({
+      id: 'ws_1',
+      orgId: 'org_1',
+      productId: 'lysnrai',
+      name: 'Operations',
+      slug: 'operations',
+      status: 'active',
+      createdAt: '2026-03-15T00:00:00.000Z',
+      updatedAt: '2026-03-15T00:00:00.000Z',
+    });
+
+    await repo.createMembership({
+      id: 'mbr_1',
+      orgId: 'org_1',
+      productId: 'lysnrai',
+      scope: 'workspace',
+      workspaceId: 'ws_1',
+      userId: 'user_2',
+      role: 'member',
+      status: 'active',
+      createdAt: '2026-03-15T00:00:00.000Z',
+      updatedAt: '2026-03-15T00:00:00.000Z',
+    });
+
+    const orgs = await repo.listOrganizations('lysnrai', { limit: 20 });
+    const workspaces = await repo.listWorkspaces('org_1');
+    const memberships = await repo.listMemberships('org_1', { limit: 100 });
+
+    expect(orgs).toHaveLength(1);
+    expect(workspaces[0].name).toBe('Operations');
+    expect(memberships[0].workspaceId).toBe('ws_1');
+  });
+});
diff --git a/services/platform-service/src/modules/orgs/repository.ts b/services/platform-service/src/modules/orgs/repository.ts
new file mode 100644
index 00000000..81f454b8
--- /dev/null
+++ b/services/platform-service/src/modules/orgs/repository.ts
@@ -0,0 +1,128 @@
+import { NotFoundError } from '../../lib/errors.js';
+import { getCollection } from '../../lib/datastore.js';
+import type {
+  ListMembershipsQuery,
+  ListOrganizationsQuery,
+  MembershipDoc,
+  OrganizationDoc,
+  WorkspaceDoc,
+} from './types.js';
+
+function orgCollection() {
+  return getCollection<OrganizationDoc>('organizations', '/productId');
+}
+
+function workspaceCollection() {
+  return getCollection<WorkspaceDoc>('workspaces', '/orgId');
+}
+
+function membershipCollection() {
+  return getCollection<MembershipDoc>('org_memberships', '/orgId');
+}
+
+export async function createOrganization(doc: OrganizationDoc): Promise<OrganizationDoc> {
+  return orgCollection().create(doc);
+}
+
+export async function listOrganizations(
+  productId: string,
+  query: ListOrganizationsQuery
+): Promise<OrganizationDoc[]> {
+  return orgCollection().findMany({
+    filter: {
+      productId,
+      ...(query.status ? { status: query.status } : {}),
+    },
+    sort: { createdAt: -1 },
+    limit: query.limit,
+  });
+}
+
+export async function getOrganization(id: string, productId: string): Promise<OrganizationDoc> {
+  const org = await orgCollection().findById(id, productId);
+  if (!org) throw new NotFoundError(`Organization '${id}' not found`);
+  return org;
+}
+
+export async function updateOrganization(
+  id: string,
+  productId: string,
+  updates: Partial<OrganizationDoc>
+): Promise<OrganizationDoc> {
+  const updated = await orgCollection().update(id, productId, {
+    ...updates,
+    updatedAt: new Date().toISOString(),
+  });
+  if (!updated) throw new NotFoundError(`Organization '${id}' not found`);
+  return updated;
+}
+
+export async function createWorkspace(doc: WorkspaceDoc): Promise<WorkspaceDoc> {
+  return workspaceCollection().create(doc);
+}
+
+export async function listWorkspaces(orgId: string): Promise<WorkspaceDoc[]> {
+  return workspaceCollection().findMany({
+    filter: { orgId },
+    sort: { createdAt: -1 },
+    limit: 100,
+  });
+}
+
+export async function getWorkspace(id: string, orgId: string): Promise<WorkspaceDoc> {
+  const workspace = await workspaceCollection().findById(id, orgId);
+  if (!workspace) throw new NotFoundError(`Workspace '${id}' not found`);
+  return workspace;
+}
+
+export async function updateWorkspace(
+  id: string,
+  orgId: string,
+  updates: Partial<WorkspaceDoc>
+): Promise<WorkspaceDoc> {
+  const updated = await workspaceCollection().update(id, orgId, {
+    ...updates,
+    updatedAt: new Date().toISOString(),
+  });
+  if (!updated) throw new NotFoundError(`Workspace '${id}' not found`);
+  return updated;
+}
+
+export async function createMembership(doc: MembershipDoc): Promise<MembershipDoc> {
+  return membershipCollection().create(doc);
+}
+
+export async function listMemberships(
+  orgId: string,
+  query: ListMembershipsQuery
+): Promise<MembershipDoc[]> {
+  const memberships = await membershipCollection().findMany({
+    filter: {
+      orgId,
+      ...(query.scope ? { scope: query.scope } : {}),
+      ...(query.workspaceId ? { workspaceId: query.workspaceId } : {}),
+    },
+    sort: { createdAt: -1 },
+    limit: query.limit,
+  });
+  return memberships;
+}
+
+export async function getMembership(id: string, orgId: string): Promise<MembershipDoc> {
+  const membership = await membershipCollection().findById(id, orgId);
+  if (!membership) throw new NotFoundError(`Membership '${id}' not found`);
+  return membership;
+}
+
+export async function updateMembership(
+  id: string,
+  orgId: string,
+  updates: Partial<MembershipDoc>
+): Promise<MembershipDoc> {
+  const updated = await membershipCollection().update(id, orgId, {
+    ...updates,
+    updatedAt: new Date().toISOString(),
+  });
+  if (!updated) throw new NotFoundError(`Membership '${id}' not found`);
+  return updated;
+}
diff --git a/services/platform-service/src/modules/orgs/routes.test.ts b/services/platform-service/src/modules/orgs/routes.test.ts
new file mode 100644
index 00000000..ec6f3ae4
--- /dev/null
+++ b/services/platform-service/src/modules/orgs/routes.test.ts
@@ -0,0 +1,80 @@
+import Fastify from 'fastify';
+import { afterEach, beforeEach, describe, expect, it, vi } from 'vitest';
+
+const repoMock = {
+  createOrganization: vi.fn(),
+  listOrganizations: vi.fn(),
+  getOrganization: vi.fn(),
+  updateOrganization: vi.fn(),
+  createWorkspace: vi.fn(),
+  listWorkspaces: vi.fn(),
+  getWorkspace: vi.fn(),
+  updateWorkspace: vi.fn(),
+  createMembership: vi.fn(),
+  listMemberships: vi.fn(),
+  updateMembership: vi.fn(),
+};
+
+vi.mock('./repository.js', () => repoMock);
+
+async function buildApp(payload?: { sub: string; productId: string; role?: string }) {
+  const { orgRoutes } = await import('./routes.js');
+  const app = Fastify({ logger: false });
+  if (payload) {
+    app.addHook('onRequest', async req => {
+      req.jwtPayload = payload;
+    });
+  }
+  await app.register(orgRoutes, { prefix: '/api' });
+  return app;
+}
+
+describe('orgRoutes', () => {
+  beforeEach(() => {
+    vi.clearAllMocks();
+  });
+
+  afterEach(() => {
+    vi.restoreAllMocks();
+  });
+
+  it('POST /orgs creates an organization and owner membership', async () => {
+    repoMock.createOrganization.mockResolvedValue({
+      id: 'org_1',
+      name: 'Acme',
+      ownerUserId: 'admin_1',
+    });
+    repoMock.createMembership.mockResolvedValue({ id: 'mbr_1' });
+
+    const app = await buildApp({ sub: 'admin_1', productId: 'lysnrai', role: 'admin' });
+    const res = await app.inject({
+      method: 'POST',
+      url: '/api/orgs',
+      payload: { name: 'Acme', slug: 'acme' },
+    });
+
+    expect(res.statusCode).toBe(200);
+    expect(repoMock.createOrganization).toHaveBeenCalled();
+    expect(repoMock.createMembership).toHaveBeenCalledWith(
+      expect.objectContaining({
+        scope: 'org',
+        role: 'owner',
+        userId: 'admin_1',
+      })
+    );
+  });
+
+  it('POST /orgs/:id/memberships validates workspace scope', async () => {
+    repoMock.getOrganization.mockResolvedValue({ id: 'org_1' });
+    const app = await buildApp({ sub: 'admin_1', productId: 'lysnrai', role: 'admin' });
+
+    const res = await app.inject({
+      method: 'POST',
+      url: '/api/orgs/org_1/memberships',
+      payload: { userId: 'user_2', role: 'member', scope: 'workspace' },
+    });
+
+    expect(res.statusCode).toBe(400);
+    expect(repoMock.createMembership).not.toHaveBeenCalled();
+  });
+});
diff --git a/services/platform-service/src/modules/orgs/routes.ts b/services/platform-service/src/modules/orgs/routes.ts
new file mode 100644
index 00000000..2da41914
--- /dev/null
+++ b/services/platform-service/src/modules/orgs/routes.ts
@@ -0,0 +1,194 @@
+import { randomUUID } from 'node:crypto';
+import type { FastifyInstance } from 'fastify';
+import { BadRequestError, ForbiddenError } from '../../lib/errors.js';
+import * as repo from './repository.js';
+import {
+  CreateMembershipSchema,
+  CreateOrganizationSchema,
+  CreateWorkspaceSchema,
+  ListMembershipsQuerySchema,
+  ListOrganizationsQuerySchema,
+  MembershipDoc,
+  OrganizationDoc,
+  UpdateMembershipSchema,
+  UpdateOrganizationSchema,
+  UpdateWorkspaceSchema,
+  WorkspaceDoc,
+} from './types.js';
+
+function requireAdmin(req: { jwtPayload?: { sub?: string; role?: string; productId?: string } }): {
+  userId: string;
+  productId: string;
+} {
+  const payload = req.jwtPayload;
+  if (!payload?.sub) {
+    throw new ForbiddenError('Authentication required');
+  }
+  if (!payload.role || !['super_admin', 'admin'].includes(payload.role)) {
+    throw new ForbiddenError('Admin access required');
+  }
+  return {
+    userId: payload.sub,
+    productId: payload.productId ?? process.env.DEFAULT_PRODUCT_ID ?? 'lysnrai',
+  };
+}
+
+export async function orgRoutes(app: FastifyInstance) {
+  app.get('/orgs', async req => {
+    const access = requireAdmin(req);
+    const parsed = ListOrganizationsQuerySchema.safeParse(req.query);
+    if (!parsed.success) {
+      throw new BadRequestError(parsed.error.issues.map(issue => issue.message).join('; '));
+    }
+    return repo.listOrganizations(access.productId, parsed.data);
+  });
+
+  app.post('/orgs', async req => {
+    const access = requireAdmin(req);
+    const parsed = CreateOrganizationSchema.safeParse(req.body);
+    if (!parsed.success) {
+      throw new BadRequestError(parsed.error.issues.map(issue => issue.message).join('; '));
+    }
+
+    const now = new Date().toISOString();
+    const org: OrganizationDoc = {
+      id: `org_${randomUUID()}`,
+      productId: access.productId,
+      name: parsed.data.name,
+      slug: parsed.data.slug,
+      status: 'active',
+      ownerUserId: parsed.data.ownerUserId ?? access.userId,
+      metadata: parsed.data.metadata,
+      createdAt: now,
+      updatedAt: now,
+    };
+
+    const created = await repo.createOrganization(org);
+    const ownerMembership: MembershipDoc = {
+      id: `mbr_${created.id}_${created.ownerUserId}_org`,
+      orgId: created.id,
+      productId: access.productId,
+      scope: 'org',
+      userId: created.ownerUserId,
+      role: 'owner',
+      status: 'active',
+      createdAt: now,
+      updatedAt: now,
+    };
+    await repo.createMembership(ownerMembership);
+
+    return created;
+  });
+
+  app.get('/orgs/:id', async req => {
+    const access = requireAdmin(req);
+    const { id } = req.params as { id: string };
+    return repo.getOrganization(id, access.productId);
+  });
+
+  app.patch('/orgs/:id', async req => {
+    const access = requireAdmin(req);
+    const { id } = req.params as { id: string };
+    const parsed = UpdateOrganizationSchema.safeParse(req.body);
+    if (!parsed.success) {
+      throw new BadRequestError(parsed.error.issues.map(issue => issue.message).join('; '));
+    }
+    return repo.updateOrganization(id, access.productId, parsed.data);
+  });
+
+  app.get('/orgs/:id/workspaces', async req => {
+    requireAdmin(req);
+    const { id } = req.params as { id: string };
+    return repo.listWorkspaces(id);
+  });
+
+  app.post('/orgs/:id/workspaces', async req => {
+    const access = requireAdmin(req);
+    const { id } = req.params as { id: string };
+    const org = await repo.getOrganization(id, access.productId);
+    const parsed = CreateWorkspaceSchema.safeParse(req.body);
+    if (!parsed.success) {
+      throw new BadRequestError(parsed.error.issues.map(issue => issue.message).join('; '));
+    }
+
+    const now = new Date().toISOString();
+    const workspace: WorkspaceDoc = {
+      id: `ws_${randomUUID()}`,
+      orgId: org.id,
+      productId: access.productId,
+      name: parsed.data.name,
+      slug: parsed.data.slug,
+      status: 'active',
+      description: parsed.data.description,
+      metadata: parsed.data.metadata,
+      createdAt: now,
+      updatedAt: now,
+    };
+
+    return repo.createWorkspace(workspace);
+  });
+
+  app.patch('/orgs/:id/workspaces/:workspaceId', async req => {
+    requireAdmin(req);
+    const { id, workspaceId } = req.params as { id: string; workspaceId: string };
+    const parsed = UpdateWorkspaceSchema.safeParse(req.body);
+    if (!parsed.success) {
+      throw new BadRequestError(parsed.error.issues.map(issue => issue.message).join('; '));
+    }
+    return repo.updateWorkspace(workspaceId, id, parsed.data);
+  });
+
+  app.get('/orgs/:id/memberships', async req => {
+    requireAdmin(req);
+    const { id } = req.params as { id: string };
+    const parsed = ListMembershipsQuerySchema.safeParse(req.query);
+    if (!parsed.success) {
+      throw new BadRequestError(parsed.error.issues.map(issue => issue.message).join('; '));
+    }
+    return repo.listMemberships(id, parsed.data);
+  });
+
+  app.post('/orgs/:id/memberships', async req => {
+    const access = requireAdmin(req);
+    const { id } = req.params as { id: string };
+    const parsed = CreateMembershipSchema.safeParse(req.body);
+    if (!parsed.success) {
+      throw new BadRequestError(parsed.error.issues.map(issue => issue.message).join('; '));
+    }
+
+    if (parsed.data.scope === 'workspace' && !parsed.data.workspaceId) {
+      throw new BadRequestError('workspaceId is required for workspace-scoped memberships');
+    }
+
+    await repo.getOrganization(id, access.productId);
+    if (parsed.data.workspaceId) {
+      await repo.getWorkspace(parsed.data.workspaceId, id);
+    }
+
+    const now = new Date().toISOString();
+    const membership: MembershipDoc = {
+      id: `mbr_${id}_${parsed.data.userId}_${parsed.data.workspaceId ?? 'org'}`,
+      orgId: id,
+      productId: access.productId,
+      scope: parsed.data.scope,
+      workspaceId: parsed.data.workspaceId,
+      userId: parsed.data.userId,
+      role: parsed.data.role,
+      status: 'active',
+      invitedBy: parsed.data.invitedBy ?? access.userId,
+      createdAt: now,
+      updatedAt: now,
+    };
+    return repo.createMembership(membership);
+  });
+
+  app.patch('/orgs/:id/memberships/:membershipId', async req => {
+    requireAdmin(req);
+    const { id, membershipId } = req.params as { id: string; membershipId: string };
+    const parsed = UpdateMembershipSchema.safeParse(req.body);
+    if (!parsed.success) {
+      throw new BadRequestError(parsed.error.issues.map(issue => issue.message).join('; '));
+    }
+    return repo.updateMembership(membershipId, id, parsed.data);
+  });
+}
diff --git a/services/platform-service/src/modules/orgs/types.ts b/services/platform-service/src/modules/orgs/types.ts
new file mode 100644
index 00000000..e249d85b
--- /dev/null
+++ b/services/platform-service/src/modules/orgs/types.ts
@@ -0,0 +1,116 @@
+import { z } from 'zod';
+
+export const OrganizationStatusSchema = z.enum(['active', 'disabled']);
+export const WorkspaceStatusSchema = z.enum(['active', 'archived']);
+export const MembershipRoleSchema = z.enum(['owner', 'admin', 'member', 'viewer']);
+export const MembershipScopeSchema = z.enum(['org', 'workspace']);
+
+export const OrganizationSchema = z.object({
+  id: z.string().min(1),
+  productId: z.string().min(1),
+  name: z.string().min(1),
+  slug: z.string().min(1),
+  status: OrganizationStatusSchema,
+  ownerUserId: z.string().min(1),
+  metadata: z.record(z.unknown()).optional(),
+  createdAt: z.string(),
+  updatedAt: z.string(),
+});
+
+export type OrganizationDoc = z.infer<typeof OrganizationSchema> & {
+  _ts?: number;
+  _etag?: string;
+};
+
+export const WorkspaceSchema = z.object({
+  id: z.string().min(1),
+  orgId: z.string().min(1),
+  productId: z.string().min(1),
+  name: z.string().min(1),
+  slug: z.string().min(1),
+  status: WorkspaceStatusSchema,
+  description: z.string().optional(),
+  metadata: z.record(z.unknown()).optional(),
+  createdAt: z.string(),
+  updatedAt: z.string(),
+});
+
+export type WorkspaceDoc = z.infer<typeof WorkspaceSchema> & {
+  _ts?: number;
+  _etag?: string;
+};
+
+export const MembershipSchema = z.object({
+  id: z.string().min(1),
+  orgId: z.string().min(1),
+  productId: z.string().min(1),
+  scope: MembershipScopeSchema,
+  workspaceId: z.string().optional(),
+  userId: z.string().min(1),
+  role: MembershipRoleSchema,
+  status: z.enum(['active', 'invited', 'disabled']).default('active'),
+  invitedBy: z.string().optional(),
+  createdAt: z.string(),
+  updatedAt: z.string(),
+});
+
+export type MembershipDoc = z.infer<typeof MembershipSchema> & {
+  _ts?: number;
+  _etag?: string;
+};
+
+export const CreateOrganizationSchema = z.object({
+  name: z.string().min(1),
+  slug: z.string().min(1),
+  ownerUserId: z.string().min(1).optional(),
+  metadata: z.record(z.unknown()).optional(),
+});
+
+export const UpdateOrganizationSchema = z.object({
+  name: z.string().min(1).optional(),
+  slug: z.string().min(1).optional(),
+  status: OrganizationStatusSchema.optional(),
+  metadata: z.record(z.unknown()).optional(),
+});
+
+export const CreateWorkspaceSchema = z.object({
+  name: z.string().min(1),
+  slug: z.string().min(1),
+  description: z.string().optional(),
+  metadata: z.record(z.unknown()).optional(),
+});
+
+export const UpdateWorkspaceSchema = z.object({
+  name: z.string().min(1).optional(),
+  slug: z.string().min(1).optional(),
+  status: WorkspaceStatusSchema.optional(),
+  description: z.string().optional(),
+  metadata: z.record(z.unknown()).optional(),
+});
+
+export const CreateMembershipSchema = z.object({
+  userId: z.string().min(1),
+  role: MembershipRoleSchema.default('member'),
+  scope: MembershipScopeSchema.default('org'),
+  workspaceId: z.string().optional(),
+  invitedBy: z.string().optional(),
+});
+
+export const UpdateMembershipSchema = z.object({
+  role: MembershipRoleSchema.optional(),
+  status: z.enum(['active', 'invited', 'disabled']).optional(),
+});
+
+export const ListOrganizationsQuerySchema = z.object({
+  status: OrganizationStatusSchema.optional(),
+  limit: z.coerce.number().min(1).max(100).default(20),
+});
+
+export const ListMembershipsQuerySchema = z.object({
+  scope: MembershipScopeSchema.optional(),
+  workspaceId: z.string().optional(),
+  limit: z.coerce.number().min(1).max(100).default(100),
+});
+
+export type ListOrganizationsQuery = z.infer<typeof ListOrganizationsQuerySchema>;
+export type ListMembershipsQuery = z.infer<typeof ListMembershipsQuerySchema>;
diff --git a/services/platform-service/src/server.ts b/services/platform-service/src/server.ts
index b2b2fd3e..af76ee7f 100644
--- a/services/platform-service/src/server.ts
+++ b/services/platform-service/src/server.ts
@@ -24,6 +24,7 @@ import { createServiceApp, registerOptionalJwtContext, startService } from '@byt
 import { productRoutes } from './modules/products/routes.js';
 import { loadProductCache } from './modules/products/cache.js';
 import { authRoutes } from './modules/auth/routes.js';
+import { orgRoutes } from './modules/orgs/routes.js';
 import { oauthRoutes } from './modules/auth/oauth/routes.js';
 import { mfaRoutes } from './modules/auth/mfa/routes.js';
 import { passkeyRoutes } from './modules/auth/passkeys/routes.js';
@@ -126,6 +127,7 @@ await registerOptionalApiKeyContext(app);
 // Register route modules
 await app.register(productRoutes, { prefix: '/api' });
 await app.register(authRoutes, { prefix: '/api' });
+await app.register(orgRoutes, { prefix: '/api' });
 await app.register(oauthRoutes, { prefix: '/api' });
 await app.register(mfaRoutes, { prefix: '/api' });
 await app.register(passkeyRoutes, { prefix: '/api' });