diff --git a/generator/integration-tests/basics/1.dart b/generator/integration-tests/basics/1.dart
index e3f8d093..c35cf8de 100644
--- a/generator/integration-tests/basics/1.dart
+++ b/generator/integration-tests/basics/1.dart
@@ -33,6 +33,11 @@ void main() {
 
     expect(entity(model, 'D').flags, equals(OBXEntityFlags.SYNC_ENABLED));
     expect(entity(jsonModel, 'D').flags, equals(OBXEntityFlags.SYNC_ENABLED));
+
+    expect(entity(model, 'E').flags,
+        equals(OBXEntityFlags.SYNC_ENABLED | OBXEntityFlags.SHARED_GLOBAL_IDS));
+    expect(entity(jsonModel, 'E').flags,
+        equals(OBXEntityFlags.SYNC_ENABLED | OBXEntityFlags.SHARED_GLOBAL_IDS));
   });
 
   test('types', () {
diff --git a/generator/integration-tests/basics/lib/lib.dart b/generator/integration-tests/basics/lib/lib.dart
index 64b09186..d612ae6a 100644
--- a/generator/integration-tests/basics/lib/lib.dart
+++ b/generator/integration-tests/basics/lib/lib.dart
@@ -28,6 +28,15 @@ class D {
   D();
 }
 
+@Entity()
+@Sync(sharedGlobalIds: true)
+class E {
+  @Id(assignable: true)
+  int id = 0;
+
+  E({this.id = 0});
+}
+
 @Entity()
 class T {
   int? id;
diff --git a/generator/lib/src/entity_resolver.dart b/generator/lib/src/entity_resolver.dart
index 8af69d52..f5e3d9f7 100644
--- a/generator/lib/src/entity_resolver.dart
+++ b/generator/lib/src/entity_resolver.dart
@@ -68,10 +68,13 @@ class EntityResolver extends Builder {
         null,
         uidRequest: !entityUid.isNull && entityUid.intValue == 0);
 
-    // Sync: check if enabled
-    if (_syncChecker.hasAnnotationOfExact(classElement)) {
+    // Sync: check if enabled and options
+    _syncChecker.runIfMatches(classElement, (annotation) {
       entity.flags |= OBXEntityFlags.SYNC_ENABLED;
-    }
+      if (annotation.getField('sharedGlobalIds')!.toBoolValue()!) {
+        entity.flags |= OBXEntityFlags.SHARED_GLOBAL_IDS;
+      }
+    });
 
     log.info(entity);
 
diff --git a/generator/test/code_builder_test.dart b/generator/test/code_builder_test.dart
index a4c02ddf..8bfd7b0e 100644
--- a/generator/test/code_builder_test.dart
+++ b/generator/test/code_builder_test.dart
@@ -352,6 +352,31 @@ void main() {
       expect(vectorProperty.hnswParams!.reparationBacklinkProbability, 0.95);
       expect(vectorProperty.hnswParams!.vectorCacheHintSizeKB, 2097152);
     });
+
+    test('Sync annotation with shared global IDs', () async {
+      final source = r'''
+      library example;     
+      import 'package:objectbox/objectbox.dart';
+      
+      @Entity()
+      @Sync(sharedGlobalIds: true)
+      class Example {
+        @Id(assignable: true)
+        int id = 0;
+      }
+      ''';
+
+      final testEnv = GeneratorTestEnv();
+      await testEnv.run(source);
+
+      // Assert final model created by generator
+      var entity = testEnv.model.entities[0];
+      expect(entity.flags & OBXEntityFlags.SYNC_ENABLED != 0, true);
+      expect(entity.flags & OBXEntityFlags.SHARED_GLOBAL_IDS != 0, true);
+      // Only a single property
+      final idProperty = testEnv.model.entities[0].properties[0];
+      expect(idProperty.flags & OBXPropertyFlags.ID_SELF_ASSIGNABLE != 0, true);
+    });
   });
 }
 
diff --git a/objectbox/CHANGELOG.md b/objectbox/CHANGELOG.md
index 81fda078..3e4cd662 100644
--- a/objectbox/CHANGELOG.md
+++ b/objectbox/CHANGELOG.md
@@ -1,5 +1,7 @@
 ## latest
 
+* Sync: support option to enable [shared global IDs](https://sync.objectbox.io/advanced/object-ids#shared-global-ids).
+
 ## 4.0.1 (2024-05-27)
 
 * Export `ObjectWithScore` and `IdWithScore` used by the new find with score `Query` methods. [#637](https://github.com/objectbox/objectbox-dart/issues/637)
diff --git a/objectbox/lib/src/native/sync.dart b/objectbox/lib/src/native/sync.dart
index c43215fd..e09985aa 100644
--- a/objectbox/lib/src/native/sync.dart
+++ b/objectbox/lib/src/native/sync.dart
@@ -583,13 +583,33 @@ class _SyncListenerGroup<StreamValueType> {
   }
 }
 
+// Note: because in Dart can't have two classes exported with the same name,
+// this class doubles as the annotation class (compare annotations.dart) and
+// configuration class for Sync.
+
 /// [ObjectBox Sync](https://objectbox.io/sync/) makes data available and
 /// synchronized across devices, online and offline.
 ///
 /// Start a client using [Sync.client()] and connect to a remote server.
 class Sync {
-  /// Create a Sync annotation, enabling synchronization for an entity.
-  const Sync();
+  /// Set to `true` to enable shared global IDs for a Sync-enabled entity class.
+  ///
+  /// By default, each Sync client has its own local ID space for Objects.
+  /// IDs are mapped to global IDs when syncing behind the scenes.
+  /// Turn this on to treat Object IDs as global and turn of ID mapping.
+  /// The ID of an Object will then be the same on all clients.
+  ///
+  /// When using this, it is recommended to use assignable IDs (`@Id(assignable: true)`)
+  /// to turn off automatically assigned IDs. Without special care, two Sync
+  /// clients are likely to overwrite each others Objects if IDs are assigned
+  /// automatically.
+  final bool sharedGlobalIds;
+
+  /// Enables sync for an `@Entity` class.
+  ///
+  /// Note that currently sync can not be enabled or disabled for existing entities.
+  /// Also synced entities can not have relations to non-synced entities.
+  const Sync({this.sharedGlobalIds = false});
 
   static final bool _syncAvailable = C.has_feature(OBXFeature.Sync);