diff --git a/Svelto.ECS/DataStructures/TypeSafeDictionary.cs b/Svelto.ECS/DataStructures/TypeSafeDictionary.cs
index 0015195..9149c71 100644
--- a/Svelto.ECS/DataStructures/TypeSafeDictionary.cs
+++ b/Svelto.ECS/DataStructures/TypeSafeDictionary.cs
@@ -20,7 +20,7 @@ namespace Svelto.ECS.Internal
         void RemoveEntitiesFromEngines(Dictionary<Type, FasterList<IHandleEntityViewEngineAbstracted>>
                                            entityViewEnginesDB);
 
-        void MoveEntityFromDictionaryAndEngines(EGID                                  fromEntityGid,
+        void MoveEntityFromDictionaryAndEngines(EGID fromEntityGid, int toGroupID,
                                                 ITypeSafeDictionary toGroup,
                                                   Dictionary<Type, FasterList<IHandleEntityViewEngineAbstracted>>
                                                       entityViewEnginesDB);
@@ -84,7 +84,7 @@ namespace Svelto.ECS.Internal
                     (entityViewsEngines[i] as IHandleEntityStructEngine<TValue>).AddInternal(ref entity);
         }
 
-        public void MoveEntityFromDictionaryAndEngines(EGID fromEntityGid, ITypeSafeDictionary toGroup,
+        public void MoveEntityFromDictionaryAndEngines(EGID fromEntityGid, int toGroupID, ITypeSafeDictionary toGroup,
                                                          Dictionary<Type, FasterList<IHandleEntityViewEngineAbstracted>>
                                                              entityViewEnginesDB)
         {
@@ -97,6 +97,7 @@ namespace Svelto.ECS.Internal
             if (toGroup != null)
             {
                 var toGroupCasted = (toGroup as TypeSafeDictionary<TValue>);
+                fasterValuesBuffer[valueIndex].ID = new EGID(fromEntityGid.entityID, toGroupID);
                 toGroupCasted.Add(fromEntityGid.entityID, ref fasterValuesBuffer[valueIndex]);
                 
                 if (entityViewEnginesDB != null)
diff --git a/Svelto.ECS/EnginesRoot.Engines.cs b/Svelto.ECS/EnginesRoot.Engines.cs
index b7f666a..e2b9f4a 100644
--- a/Svelto.ECS/EnginesRoot.Engines.cs
+++ b/Svelto.ECS/EnginesRoot.Engines.cs
@@ -43,7 +43,7 @@ namespace Svelto.ECS
             {
                 [ExclusiveGroup.StandardEntitiesGroup] = new Dictionary<Type, ITypeSafeDictionary>()
             };
-            _groupedGroups = new Dictionary<Type, FasterDictionary<int, int>>();
+            //_groupedGroups = new Dictionary<Type, FasterDictionary<int, int>>();
             _groupedEntityToAdd = new DoubleBufferedEntityViews<Dictionary<int, Dictionary<Type, ITypeSafeDictionary>>>();
 
             _DB = new entitiesDB(_groupEntityDB);
diff --git a/Svelto.ECS/EnginesRoot.Entities.cs b/Svelto.ECS/EnginesRoot.Entities.cs
index be9d6e1..05122d2 100644
--- a/Svelto.ECS/EnginesRoot.Entities.cs
+++ b/Svelto.ECS/EnginesRoot.Entities.cs
@@ -108,28 +108,28 @@ namespace Svelto.ECS
         
         ///--------------------------------------------
         /// 
-        void MoveEntity(EGID entityGID, Dictionary<Type, ITypeSafeDictionary> toGroup = null)
+        void MoveEntity(EGID entityGID, int toGroupID = -1, Dictionary<Type, ITypeSafeDictionary> toGroup = null)
         {
             var entityViewInfoDictionary = _groupEntityDB[entityGID.groupID][_typeEntityInfoView] as TypeSafeDictionary<EntityInfoView>;
             var entityBuilders = entityViewInfoDictionary[entityGID.entityID].entityToBuild;
             var entityBuildersCount = entityBuilders.Length;
-            var group = _groupEntityDB[entityGID.groupID];
-
+           
             //for each entity view generated by the entity descriptor
             for (var i = 0; i < entityBuildersCount; i++)
             {
                 var entityType = entityBuilders[i].GetEntityType();
-
                 
-                MoveEntity(entityGID, toGroup, @group, entityType);
+                MoveEntity(entityGID, toGroupID, toGroup, entityType);
             }
 
-            MoveEntity(entityGID, toGroup, @group, _typeEntityInfoView);
+            MoveEntity(entityGID, toGroupID, toGroup, _typeEntityInfoView);
         }
 
-        void MoveEntity(EGID entityGID, Dictionary<Type, ITypeSafeDictionary> toGroup, Dictionary<Type, ITypeSafeDictionary> @group, Type entityType)
+        void MoveEntity(EGID fromEntityGID, int toGroupID, Dictionary<Type, ITypeSafeDictionary> toGroup, Type entityType)
         {
-            var fromTypeSafeDictionary = @group[entityType];
+            var fromGroup = _groupEntityDB[fromEntityGID.groupID];
+
+            var fromTypeSafeDictionary = fromGroup[entityType];
             ITypeSafeDictionary safeDictionary = null;
 
             if (toGroup != null)
@@ -138,17 +138,18 @@ namespace Svelto.ECS
                 {
                     safeDictionary = fromTypeSafeDictionary.Create();
                     toGroup.Add(entityType, safeDictionary);
+                    //_groupedGroups[entityType] = new FasterDictionary<int, ITypeSafeDictionary>();
                 }
             }
 
-            fromTypeSafeDictionary.MoveEntityFromDictionaryAndEngines(entityGID, safeDictionary, _entityEngines);
+            fromTypeSafeDictionary.MoveEntityFromDictionaryAndEngines(fromEntityGID, toGroupID, safeDictionary, _entityEngines);
 
             if (fromTypeSafeDictionary.Count == 0) //clean up
             {
-                @group.Remove(entityType);
+                fromGroup.Remove(entityType);
             }
             
-            //it doesn't eliminate the group itself on purpose
+            //it doesn't eliminate the fromGroup itself on purpose
         }
 
         void RemoveGroupAndEntitiesFromDB(int groupID)
@@ -164,14 +165,14 @@ namespace Svelto.ECS
         void SwapEntityGroup(int entityID, int fromGroupID, int toGroupID)
         {
             DBC.ECS.Check.Require(fromGroupID != toGroupID,
-                          "can't move an entity to the same group where it already belongs to");
+                          "can't move an entity to the same fromGroup where it already belongs to");
 
             Dictionary<Type, ITypeSafeDictionary> toGroup;
-            
+
             if (_groupEntityDB.TryGetValue(toGroupID, out toGroup) == false)
                 toGroup = _groupEntityDB[toGroupID] = new Dictionary<Type, ITypeSafeDictionary>();
 
-            MoveEntity(new EGID(entityID, fromGroupID), toGroup);
+            MoveEntity(new EGID(entityID, fromGroupID), toGroupID, toGroup);
         }
         
         EGID SwapFirstEntityGroup(int fromGroupID, int toGroupId)
@@ -185,8 +186,8 @@ namespace Svelto.ECS
         }
 
         readonly entitiesDB                                                _DB;
-        readonly Dictionary<int, Dictionary<Type, ITypeSafeDictionary>>    _groupEntityDB;
-        readonly Dictionary<Type, FasterDictionary<int, int>>              _groupedGroups; //yes I am being sarcastic
+        readonly DoubleBufferedEntityViews<Dictionary<int, Dictionary<Type, ITypeSafeDictionary>>> _groupedEntityToAdd;
+        
 
         static readonly Type                                               _typeEntityInfoView = typeof(EntityInfoView);
     }
diff --git a/Svelto.ECS/EnginesRoot.Submission.cs b/Svelto.ECS/EnginesRoot.Submission.cs
index f0c510f..52f7572 100644
--- a/Svelto.ECS/EnginesRoot.Submission.cs
+++ b/Svelto.ECS/EnginesRoot.Submission.cs
@@ -1,5 +1,6 @@
 using System;
 using System.Collections.Generic;
+using Svelto.DataStructures.Experimental;
 using Svelto.ECS.Internal;
 using Svelto.ECS.Schedulers;
 
@@ -63,10 +64,14 @@ namespace Svelto.ECS
                 {
                     ITypeSafeDictionary dbDic;
                     if (groupDB.TryGetValue(entityViewTypeSafeDictionary.Key, out dbDic) == false)
+                    {
                         dbDic = groupDB[entityViewTypeSafeDictionary.Key] = entityViewTypeSafeDictionary.Value.Create();
+                        //_groupedGroups[entityViewTypeSafeDictionary.Key] = new FasterDictionary<int, ITypeSafeDictionary>();
+                    }
 
                     //type safe copy
                     dbDic.FillWithIndexedEntities(entityViewTypeSafeDictionary.Value);
+                  //  _groupedGroups[entityViewTypeSafeDictionary.Key][groupID] = dbDic;
                 }
             }
 
@@ -86,7 +91,9 @@ namespace Svelto.ECS
         //split by type per group. It's possible to get all the entities of a give type T per group thanks 
         //to the FasterDictionary capabilitiies OR it's possible to get a specific entityView indexed by
         //ID. This ID doesn't need to be the EGID, it can be just the entityID
-        readonly DoubleBufferedEntityViews<Dictionary<int, Dictionary<Type, ITypeSafeDictionary>>>    _groupedEntityToAdd;
+        
+        readonly Dictionary<int, Dictionary<Type, ITypeSafeDictionary>> _groupEntityDB;
+//        readonly Dictionary<Type, FasterDictionary<int, ITypeSafeDictionary>> _groupedGroups; //yes I am being sarcastic
         readonly EntitySubmissionScheduler                                                            _scheduler;
     }
 }
\ No newline at end of file