diff --git a/source/model/meshinstance.js b/source/model/meshinstance.js
index a0c8546..15a7f8b 100644
--- a/source/model/meshinstance.js
+++ b/source/model/meshinstance.js
@@ -19,13 +19,19 @@ OV.MeshInstanceId = class
 
 OV.MeshInstance = class extends OV.ModelObject3D
 {
-    constructor (node, mesh)
+    constructor (id, node, mesh)
     {
         super ();
+        this.id = id;
         this.node = node;
         this.mesh = mesh;
     }
 
+    GetId ()
+    {
+        return this.id;
+    }
+
     VertexCount ()
     {
         return this.mesh.VertexCount ();
diff --git a/source/model/model.js b/source/model/model.js
index b2964f2..31bad71 100644
--- a/source/model/model.js
+++ b/source/model/model.js
@@ -128,7 +128,8 @@ OV.Model = class extends OV.ModelObject3D
             return null;
         }
         let foundMesh = this.GetMesh (instanceId.meshIndex);
-        return new OV.MeshInstance (foundNode, foundMesh);
+        let id = new OV.MeshInstanceId (foundNode.GetId (), instanceId.meshIndex);
+        return new OV.MeshInstance (id, foundNode, foundMesh);
     }
 
     EnumerateMeshes (onMesh)
@@ -142,8 +143,9 @@ OV.Model = class extends OV.ModelObject3D
     {
         this.root.Enumerate ((node) => {
             for (let meshIndex of node.GetMeshIndices ()) {
+                let id = new OV.MeshInstanceId (node.GetId (), meshIndex);
                 let mesh = this.GetMesh (meshIndex);
-                let meshInstance = new OV.MeshInstance (node, mesh);
+                let meshInstance = new OV.MeshInstance (id, node, mesh);
                 onMeshInstance (meshInstance);
             }
         });
diff --git a/test/tests/model_test.js b/test/tests/model_test.js
index eea9892..124b8ca 100644
--- a/test/tests/model_test.js
+++ b/test/tests/model_test.js
@@ -403,4 +403,15 @@ describe ('Node Hierarchy', function () {
         assert.strictEqual (model.TextureUVCount (), 0);
         assert.strictEqual (model.TriangleCount (), 12 * 3);
     });
+
+    it ('Instance enumeration', function () {
+        let model = testUtils.GetTranslatedRotatedCubesModel ();
+        let meshInstances = [];
+        model.EnumerateMeshInstances ((meshInstance) => {
+            meshInstances.push (meshInstance);
+        });
+        assert (meshInstances[0].GetId ().IsEqual (new OV.MeshInstanceId (0, 0)));
+        assert (meshInstances[1].GetId ().IsEqual (new OV.MeshInstanceId (1, 0)));
+        assert (meshInstances[2].GetId ().IsEqual (new OV.MeshInstanceId (3, 0)));
+    });
 });
diff --git a/test/tests/modelutils_test.js b/test/tests/modelutils_test.js
index ae5c417..0e80b67 100644
--- a/test/tests/modelutils_test.js
+++ b/test/tests/modelutils_test.js
@@ -14,7 +14,7 @@ describe ('Model Utils', function () {
         let transformation = new OV.Transformation (new OV.Matrix ().CreateTranslation (2.0, 0.0, 0.0));
         let node = new OV.Node ();
         node.SetTransformation (transformation);
-        let cubeInstance = new OV.MeshInstance (node, cube);
+        let cubeInstance = new OV.MeshInstance (null, node, cube);
         let cubeInstanceBounds = OV.GetBoundingBox (cubeInstance);
         assert (OV.CoordIsEqual3D (cubeInstanceBounds.min, new OV.Coord3D (2.0, 0.0, 0.0)));
         assert (OV.CoordIsEqual3D (cubeInstanceBounds.max, new OV.Coord3D (3.0, 1.0, 1.0)));
diff --git a/test/tests/quantities_test.js b/test/tests/quantities_test.js
index f30cc34..c997051 100644
--- a/test/tests/quantities_test.js
+++ b/test/tests/quantities_test.js
@@ -105,7 +105,7 @@ describe ('Quantities', function () {
         const transformation = new OV.Transformation (new OV.Matrix ().CreateScale (2.0, 2.0, 2.0));
         let node = new OV.Node ();
         node.SetTransformation (transformation);
-        const meshInstance = new OV.MeshInstance (node, mesh);
+        const meshInstance = new OV.MeshInstance (null, node, mesh);
         assert (OV.IsSolid (meshInstance));
         assert (OV.IsEqual (OV.CalculateVolume (meshInstance), 8.0));
         assert (OV.IsEqual (OV.CalculateSurfaceArea (meshInstance), 24.0));