diff --git a/docs/route-access-matrix.md b/docs/route-access-matrix.md
index d4cc1e7..19bccf5 100644
--- a/docs/route-access-matrix.md
+++ b/docs/route-access-matrix.md
@@ -146,7 +146,7 @@ Reasoning:
 
 ### `packages/api/src/router/blueprint.ts`
 
-- `listSummaries`, `list`, `getById`, `getByIdentifier`: `planning-read`
+- `listSummaries`, `list`, `getById`, `getByIdentifier`, `getGlobalFieldDefs`: `planning-read`
 - `resolveByIdentifier`: `authenticated-safe-lookup`
 - create, update, delete, global-flag writes: `admin-only`
 
@@ -155,6 +155,7 @@ Reasoning:
 - `listSummaries` exposes `_count.projects`, so the assistant-facing summary list should not remain a broad authenticated read
 - `resolveByIdentifier` already returns a narrow lookup shape suitable for low-risk name/id resolution
 - the broader blueprint reads expose full template configuration such as field definitions, defaults, and validation rules that belong to planning workflows rather than generic authenticated access
+- `getGlobalFieldDefs` aggregates active global field definitions across blueprints, so it belongs with the same planning configuration audience rather than a broad authenticated read
 
 ### `packages/api/src/router/holiday-calendar.ts`
 
diff --git a/packages/api/src/__tests__/master-data-router-auth.test.ts b/packages/api/src/__tests__/master-data-router-auth.test.ts
index 79970d8..37aac83 100644
--- a/packages/api/src/__tests__/master-data-router-auth.test.ts
+++ b/packages/api/src/__tests__/master-data-router-auth.test.ts
@@ -26,6 +26,14 @@ function createProtectedContext(
   };
 }
 
+function createUnauthenticatedContext(db: Record<string, unknown>) {
+  return {
+    session: null,
+    db: db as never,
+    dbUser: null,
+  };
+}
+
 describe("master-data router authorization", () => {
   it("requires planning read access for blueprint summaries with project counts", async () => {
     const findMany = vi.fn();
@@ -166,6 +174,75 @@ describe("master-data router authorization", () => {
     });
   });
 
+  it("requires authenticated planning access for global blueprint field definitions", async () => {
+    const findMany = vi.fn();
+
+    const unauthenticatedCaller = createCallerFactory(blueprintRouter)(createUnauthenticatedContext({
+      blueprint: {
+        findMany,
+      },
+    }));
+    const authenticatedCaller = createCallerFactory(blueprintRouter)(createProtectedContext({
+      blueprint: {
+        findMany,
+      },
+    }));
+
+    await expect(unauthenticatedCaller.getGlobalFieldDefs({ target: BlueprintTarget.PROJECT })).rejects.toMatchObject({
+      code: "UNAUTHORIZED",
+      message: "Authentication required",
+    });
+    await expect(authenticatedCaller.getGlobalFieldDefs({ target: BlueprintTarget.PROJECT })).rejects.toMatchObject({
+      code: "FORBIDDEN",
+      message: "Planning read access required",
+    });
+
+    expect(findMany).not.toHaveBeenCalled();
+  });
+
+  it("allows global blueprint field definitions for users with planning access", async () => {
+    const findMany = vi.fn().mockResolvedValue([
+      {
+        id: "bp_project_global",
+        name: "Global Project Blueprint",
+        fieldDefs: [
+          { key: "market", label: "Market", type: "text" },
+          { key: "deliveryModel", label: "Delivery Model", type: "select" },
+        ],
+      },
+    ]);
+    const caller = createCallerFactory(blueprintRouter)(createProtectedContext({
+      blueprint: {
+        findMany,
+      },
+    }, {
+      granted: [PermissionKey.VIEW_PLANNING],
+    }));
+
+    const result = await caller.getGlobalFieldDefs({ target: BlueprintTarget.PROJECT });
+
+    expect(result).toEqual([
+      {
+        key: "market",
+        label: "Market",
+        type: "text",
+        blueprintId: "bp_project_global",
+        blueprintName: "Global Project Blueprint",
+      },
+      {
+        key: "deliveryModel",
+        label: "Delivery Model",
+        type: "select",
+        blueprintId: "bp_project_global",
+        blueprintName: "Global Project Blueprint",
+      },
+    ]);
+    expect(findMany).toHaveBeenCalledWith({
+      where: { target: "PROJECT", isGlobal: true, isActive: true },
+      select: { id: true, name: true, fieldDefs: true },
+    });
+  });
+
   it("keeps country lists available to authenticated users as safe lookup data", async () => {
     const findMany = vi.fn().mockResolvedValue([
       {
diff --git a/packages/api/src/router/blueprint.ts b/packages/api/src/router/blueprint.ts
index 44d2afa..ce00c68 100644
--- a/packages/api/src/router/blueprint.ts
+++ b/packages/api/src/router/blueprint.ts
@@ -247,7 +247,7 @@ export const blueprintRouter = createTRPCRouter({
       return { count: updated.length };
     }),
 
-  getGlobalFieldDefs: protectedProcedure
+  getGlobalFieldDefs: planningReadProcedure
     .input(z.object({ target: z.nativeEnum(BlueprintTarget) }))
     .query(async ({ ctx, input }) => {
       const blueprints = await ctx.db.blueprint.findMany({