diff --git a/tools/apiview/emitters/cadl-apiview/src/apiview.ts b/tools/apiview/emitters/cadl-apiview/src/apiview.ts
index 97d596d132ac..a103706b2bca 100644
--- a/tools/apiview/emitters/cadl-apiview/src/apiview.ts
+++ b/tools/apiview/emitters/cadl-apiview/src/apiview.ts
@@ -319,7 +319,6 @@ export class ApiView {
     if (name === this.packageName) {
       return true;
     }
-    // FIXME: This should actually ensure that it is a proper subnamespace
     if (!name.startsWith(this.packageName)) {
       return false;
     }
@@ -343,7 +342,9 @@ export class ApiView {
       if (!this.shouldEmitNamespace(name)) {
         continue;
       }
-      const nsModel = new NamespaceModel(name, ns, program);
+      // use a fake name to make the global namespace clear
+      const namespaceName = name == "" ? "::GLOBAL::" : name;
+      const nsModel = new NamespaceModel(namespaceName, ns, program);
       if (nsModel.shouldEmit()) {
         this.tokenizeNamespaceModel(nsModel);
         this.buildNavigation(nsModel);  
diff --git a/tools/apiview/emitters/cadl-apiview/test/apiview-options.test.ts b/tools/apiview/emitters/cadl-apiview/test/apiview-options.test.ts
index f5782f4de699..29ea0a74afb1 100644
--- a/tools/apiview/emitters/cadl-apiview/test/apiview-options.test.ts
+++ b/tools/apiview/emitters/cadl-apiview/test/apiview-options.test.ts
@@ -1,7 +1,7 @@
 import { Diagnostic, logDiagnostics, resolvePath } from "@cadl-lang/compiler";
-import { expectDiagnosticEmpty } from "@cadl-lang/compiler/testing";
+import { expectDiagnosticEmpty, expectDiagnostics } from "@cadl-lang/compiler/testing";
 import { strictEqual } from "assert";
-import { apiViewFor, apiViewText, compare } from "./test-host.js";
+import { apiViewFor, apiViewText, compare, createApiViewTestRunner, diagnosticsFor } from "./test-host.js";
 
 describe("apiview-options: tests", () => {
 
@@ -44,8 +44,16 @@ describe("apiview-options: tests", () => {
     }
     `;
     const expect = `
-    model SomeGlobal {};
+    namespace ::GLOBAL:: {
+      model SomeGlobal {}
+    }
 
+    @Cadl.service(
+      {
+        title: "Test";
+        version: "1";
+      }
+    )
     namespace Azure.Test {
       model Foo {}
     }
@@ -54,7 +62,53 @@ describe("apiview-options: tests", () => {
       "include-global-namespace": true
     });
     const actual = apiViewText(apiview);
-    compare(expect, actual, 9);
+    compare(expect, actual, 1);
   });
 
+  it("emits error if multi-service package tries to specify version", async () => {
+    const input = `
+    @Cadl.service( { title: "Test", version: "1" } )
+    namespace Azure.Test {
+      model Foo {};
+    }
+
+    @Cadl.service( { title: "OtherTest", version: "1" } )
+    namespace Azure.OtherTest {
+      model Foo {};
+    }
+    `
+    const diagnostics = await diagnosticsFor(input, {"version": "1"});
+    expectDiagnostics(diagnostics, [
+      {
+        code: "@azure-tools/cadl-apiview/invalid-option",
+        message: `Option "--output-file" cannot be used with multi-service specs unless "--service" is also supplied.`
+      },
+      {
+        code: "@azure-tools/cadl-apiview/invalid-option",
+        message: `Option "--version" cannot be used with multi-service specs unless "--service" is also supplied.`
+      }
+    ]);
+  });
+
+  it("allows options if multi-service package specifies --service", async () => {
+    const input = `
+    @Cadl.service( { title: "Test", version: "1" } )
+    namespace Azure.Test {
+      model Foo {};
+    }
+
+    @Cadl.service( { title: "OtherTest", version: "1" } )
+    namespace Azure.OtherTest {
+      model Foo {};
+    }
+    `;
+    const expect = `
+    namespace Azure.OtherTest {
+      model Foo {}
+    }
+    `;
+    const apiview = await apiViewFor(input, {"version": "1", "service": "OtherTest"});
+    const actual = apiViewText(apiview);
+    compare(expect, actual, 9);
+  });
 });
diff --git a/tools/apiview/emitters/cadl-apiview/test/test-host.ts b/tools/apiview/emitters/cadl-apiview/test/test-host.ts
index ac7e61312e98..6f030ba197b8 100644
--- a/tools/apiview/emitters/cadl-apiview/test/test-host.ts
+++ b/tools/apiview/emitters/cadl-apiview/test/test-host.ts
@@ -6,7 +6,7 @@ import { ApiViewTestLibrary } from "../src/testing/index.js";
 import "@azure-tools/cadl-apiview";
 import { ApiViewEmitterOptions } from "../src/lib.js";
 import { ApiViewDocument, ApiViewTokenKind } from "../src/apiview.js";
-import { resolvePath } from "@cadl-lang/compiler";
+import { Diagnostic, resolvePath } from "@cadl-lang/compiler";
 import { strictEqual } from "assert";
 
 export async function createApiViewTestHost() {
@@ -34,6 +34,17 @@ export async function createApiViewTestRunner({
   });
 }
 
+export async function diagnosticsFor(code: string, options: ApiViewEmitterOptions): Promise<readonly Diagnostic[]> {
+  const runner = await createApiViewTestRunner({withVersioning: true});
+  const outPath = resolvePath("/apiview.json");
+  const diagnostics = await runner.diagnose(code, {
+    noEmit: false,
+    emitters: { "@azure-tools/cadl-apiview": { ...options, "output-file": outPath } },
+    miscOptions: { "disable-linter": true },
+  });
+  return diagnostics;
+}
+
 export async function apiViewFor(code: string, options: ApiViewEmitterOptions): Promise<ApiViewDocument> {
   const runner = await createApiViewTestRunner({withVersioning: true});
   const outPath = resolvePath("/apiview.json");