diff --git a/src/domain/definitions/definition.ts b/src/domain/definitions/definition.ts
index 553936bc..eda77fae 100644
--- a/src/domain/definitions/definition.ts
+++ b/src/domain/definitions/definition.ts
@@ -149,12 +149,19 @@ export const DefinitionSchema = z.object({
   ),
   id: z.string().uuid(),
   name: z.string().min(1).refine(
-    (name) =>
-      !name.includes("..") && !name.includes("/") && !name.includes("\\") &&
-      !name.includes("\0"),
+    (name) => {
+      if (name.includes("..") || name.includes("\\") || name.includes("\0")) {
+        return false;
+      }
+      if (name.includes("/")) {
+        // Allow '/' only in scoped @collective/name extension names
+        return /^@[a-z0-9_-]+\/[a-z0-9_-]+(\/[a-z0-9_-]+)*$/.test(name);
+      }
+      return true;
+    },
     {
       message:
-        "Definition name must not contain '..', '/', '\\', or null bytes (path traversal)",
+        "Definition name must not contain '..', '\\', or null bytes (path traversal). '/' is only allowed in scoped @collective/name patterns.",
     },
   ),
   version: z.number().int().positive(),
diff --git a/src/domain/definitions/definition_test.ts b/src/domain/definitions/definition_test.ts
index 4399ffec..670b69a7 100644
--- a/src/domain/definitions/definition_test.ts
+++ b/src/domain/definitions/definition_test.ts
@@ -140,6 +140,33 @@ Deno.test("Definition.create throws on name with null bytes", () => {
   );
 });
 
+// Scoped @collective/name tests
+
+Deno.test("Definition.create accepts scoped @collective/name", () => {
+  const def = Definition.create({ name: "@john/pod-inventory" });
+  assertEquals(def.name, "@john/pod-inventory");
+});
+
+Deno.test("Definition.create accepts scoped name with multiple segments", () => {
+  const def = Definition.create({ name: "@swamp/aws/ec2" });
+  assertEquals(def.name, "@swamp/aws/ec2");
+});
+
+Deno.test("Definition.create rejects malformed scoped names", () => {
+  assertThrows(
+    () => Definition.create({ name: "@/" }),
+    Error,
+  );
+  assertThrows(
+    () => Definition.create({ name: "@scope/" }),
+    Error,
+  );
+  assertThrows(
+    () => Definition.create({ name: "@UPPER/case" }),
+    Error,
+  );
+});
+
 Deno.test("Definition.create throws on invalid version", () => {
   assertThrows(
     () => Definition.create({ name: "test", version: 0 }),
diff --git a/src/domain/workflows/workflow.ts b/src/domain/workflows/workflow.ts
index c9b86005..19bf7aa4 100644
--- a/src/domain/workflows/workflow.ts
+++ b/src/domain/workflows/workflow.ts
@@ -39,12 +39,19 @@ import {
 export const WorkflowSchema = z.object({
   id: z.string().uuid(),
   name: z.string().min(1).refine(
-    (name) =>
-      !name.includes("..") && !name.includes("/") && !name.includes("\\") &&
-      !name.includes("\0"),
+    (name) => {
+      if (name.includes("..") || name.includes("\\") || name.includes("\0")) {
+        return false;
+      }
+      if (name.includes("/")) {
+        // Allow '/' only in scoped @collective/name extension names
+        return /^@[a-z0-9_-]+\/[a-z0-9_-]+(\/[a-z0-9_-]+)*$/.test(name);
+      }
+      return true;
+    },
     {
       message:
-        "Workflow name must not contain '..', '/', '\\', or null bytes (path traversal)",
+        "Workflow name must not contain '..', '\\', or null bytes (path traversal). '/' is only allowed in scoped @collective/name patterns.",
     },
   ),
   description: z.string().optional(),
diff --git a/src/domain/workflows/workflow_test.ts b/src/domain/workflows/workflow_test.ts
index 2e8a374a..95c55013 100644
--- a/src/domain/workflows/workflow_test.ts
+++ b/src/domain/workflows/workflow_test.ts
@@ -439,6 +439,33 @@ Deno.test("Workflow.create rejects path traversal even without jobs", () => {
   );
 });
 
+// Scoped @collective/name tests
+
+Deno.test("Workflow.create accepts scoped @collective/name", () => {
+  const workflow = Workflow.create({ name: "@john/pod-inventory" });
+  assertEquals(workflow.name, "@john/pod-inventory");
+});
+
+Deno.test("Workflow.create accepts scoped name with multiple segments", () => {
+  const workflow = Workflow.create({ name: "@swamp/aws/ec2" });
+  assertEquals(workflow.name, "@swamp/aws/ec2");
+});
+
+Deno.test("Workflow.create rejects malformed scoped names", () => {
+  assertThrows(
+    () => Workflow.create({ name: "@/" }),
+    Error,
+  );
+  assertThrows(
+    () => Workflow.create({ name: "@scope/" }),
+    Error,
+  );
+  assertThrows(
+    () => Workflow.create({ name: "@UPPER/case" }),
+    Error,
+  );
+});
+
 // Driver field tests
 
 Deno.test("Workflow.create defaults driver to undefined", () => {