diff --git a/common/class_undoredo_container.cpp b/common/class_undoredo_container.cpp
index 9b4834d54b..99cf5fb76c 100644
--- a/common/class_undoredo_container.cpp
+++ b/common/class_undoredo_container.cpp
@@ -30,6 +30,16 @@
 #include "base_struct.h"
 #include "class_undoredo_container.h"
 
+
+ITEM_PICKER::ITEM_PICKER( EDA_BaseStruct* aItem, UndoRedoOpType aUndoRedoStatus )
+{
+    m_UndoRedoStatus = aUndoRedoStatus;
+    m_PickedItem = aItem;
+    m_PickedItemType = TYPE_NOT_INIT;
+    m_Link = NULL;
+}
+
+
 PICKED_ITEMS_LIST::PICKED_ITEMS_LIST()
 {
     m_Status = UR_UNSPECIFIED;
@@ -70,11 +80,17 @@ void PICKED_ITEMS_LIST::PICKED_ITEMS_LIST::ClearItemsList()
 void PICKED_ITEMS_LIST::ClearListAndDeleteItems()
 {
     for(unsigned ii = 0; ii < m_ItemsList.size(); ii++ )
-        delete m_ItemsList[ii].m_Item;
+        delete m_ItemsList[ii].m_PickedItem;
     m_ItemsList.clear();
 }
 
 
+/** function GetItemWrapper
+ * @return the picker of a picked item
+ * @param aIdx = index of the picker in the picked list
+ * if this picker does not exist, a picker is returned,
+ * with its members set to 0 or NULL
+ */
 ITEM_PICKER PICKED_ITEMS_LIST::GetItemWrapper( unsigned int aIdx )
 {
     ITEM_PICKER picker;
@@ -84,16 +100,24 @@ ITEM_PICKER PICKED_ITEMS_LIST::GetItemWrapper( unsigned int aIdx )
     return picker;
 }
 
-EDA_BaseStruct* PICKED_ITEMS_LIST::GetItemData( unsigned int aIdx )
+/** function GetPickedItem
+ * @return a pointer to the picked item, or null if does not exist
+ * @param aIdx = index of the picked item in the picked list
+ */
+EDA_BaseStruct* PICKED_ITEMS_LIST::GetPickedItem( unsigned int aIdx )
 {
     if( aIdx < m_ItemsList.size() )
-        return m_ItemsList[aIdx].m_Item;
+        return m_ItemsList[aIdx].m_PickedItem;
     else
         return NULL;
 }
 
 
-EDA_BaseStruct* PICKED_ITEMS_LIST::GetImage( unsigned int aIdx )
+/** function GetLink
+ * @return link of the picked item, or null if does not exist
+ * @param aIdx = index of the picked item in the picked list
+ */
+EDA_BaseStruct* PICKED_ITEMS_LIST::GetLink( unsigned int aIdx )
 {
     if( aIdx < m_ItemsList.size() )
         return m_ItemsList[aIdx].m_Link;
@@ -102,7 +126,12 @@ EDA_BaseStruct* PICKED_ITEMS_LIST::GetImage( unsigned int aIdx )
 }
 
 
-UndoRedoOpType PICKED_ITEMS_LIST::GetItemStatus( unsigned int aIdx )
+/** function GetPickedItemStatus
+ * @return the type of undo/redo opertaion associated to the picked item,
+ *   or UR_UNSPECIFIED if does not exist
+ * @param aIdx = index of the picked item in the picked list
+ */
+UndoRedoOpType PICKED_ITEMS_LIST::GetPickedItemStatus( unsigned int aIdx )
 {
     if( aIdx < m_ItemsList.size() )
         return m_ItemsList[aIdx].m_UndoRedoStatus;
@@ -111,11 +140,16 @@ UndoRedoOpType PICKED_ITEMS_LIST::GetItemStatus( unsigned int aIdx )
 }
 
 
-bool PICKED_ITEMS_LIST::SetItem( EDA_BaseStruct* aItem, unsigned aIdx )
+/** function SetPickedItem
+ * @param aItem = a pointer to the item to pick
+ * @param aIdx = index of the picker in the picked list
+ * @return true if the picker exists, or false if does not exist
+ */
+bool PICKED_ITEMS_LIST::SetPickedItem( EDA_BaseStruct* aItem, unsigned aIdx )
 {
     if( aIdx < m_ItemsList.size() )
     {
-        m_ItemsList[aIdx].m_Item = aItem;
+        m_ItemsList[aIdx].m_PickedItem = aItem;
         return true;
     }
     else
@@ -123,11 +157,17 @@ bool PICKED_ITEMS_LIST::SetItem( EDA_BaseStruct* aItem, unsigned aIdx )
 }
 
 
-bool PICKED_ITEMS_LIST::SetLink( EDA_BaseStruct* aItem, unsigned aIdx )
+/** function SetLink
+ * Set the link associated to a given picked item
+ * @param aLink = the link to the item associated to the picked item
+ * @param aIdx = index of the picker in the picked list
+ * @return true if the picker exists, or false if does not exist
+ */
+bool PICKED_ITEMS_LIST::SetLink( EDA_BaseStruct* aLink, unsigned aIdx )
 {
     if( aIdx < m_ItemsList.size() )
     {
-        m_ItemsList[aIdx].m_Link = aItem;
+        m_ItemsList[aIdx].m_Link = aLink;
         return true;
     }
     else
@@ -135,11 +175,17 @@ bool PICKED_ITEMS_LIST::SetLink( EDA_BaseStruct* aItem, unsigned aIdx )
 }
 
 
-bool PICKED_ITEMS_LIST::SetItem( EDA_BaseStruct* aItem, UndoRedoOpType aStatus, unsigned aIdx )
+/** function SetPickedItem
+ * @param aItem = a pointer to the item to pick
+ * @param aStatus = the type of undo/redo operation associated to the item to pick
+ * @param aIdx = index of the picker in the picked list
+ * @return true if the picker exists, or false if does not exist
+ */
+bool PICKED_ITEMS_LIST::SetPickedItem( EDA_BaseStruct* aItem, UndoRedoOpType aStatus, unsigned aIdx )
 {
     if( aIdx < m_ItemsList.size() )
     {
-        m_ItemsList[aIdx].m_Item = aItem;
+        m_ItemsList[aIdx].m_PickedItem = aItem;
         m_ItemsList[aIdx].m_UndoRedoStatus = aStatus;
         return true;
     }
@@ -148,7 +194,13 @@ bool PICKED_ITEMS_LIST::SetItem( EDA_BaseStruct* aItem, UndoRedoOpType aStatus,
 }
 
 
-bool PICKED_ITEMS_LIST::SetItemStatus( UndoRedoOpType aStatus, unsigned aIdx )
+/** function SetPickedItemStatus
+ * Set the the type of undo/redo operation for a given picked item
+ * @param aStatus = the type of undo/redo operation associated to the picked item
+ * @param aIdx = index of the picker in the picked list
+ * @return true if the picker exists, or false if does not exist
+ */
+bool PICKED_ITEMS_LIST::SetPickedItemStatus( UndoRedoOpType aStatus, unsigned aIdx )
 {
     if( aIdx < m_ItemsList.size() )
     {
@@ -160,7 +212,12 @@ bool PICKED_ITEMS_LIST::SetItemStatus( UndoRedoOpType aStatus, unsigned aIdx )
 }
 
 
-bool PICKED_ITEMS_LIST::RemoveItem( unsigned aIdx )
+/** function RemovePickedItem
+ * remùove one entry (one picker) from the list of picked items
+ * @param aIdx = index of the picker in the picked list
+ * @return true if ok, or false if did not exist
+ */
+bool PICKED_ITEMS_LIST::RemovePickedItem( unsigned aIdx )
 {
     if( aIdx >= m_ItemsList.size() )
         return false;
diff --git a/eeschema/block.cpp b/eeschema/block.cpp
index 783433778b..73c8452a11 100644
--- a/eeschema/block.cpp
+++ b/eeschema/block.cpp
@@ -479,7 +479,7 @@ static void DrawMovingBlockOutlines( WinEDA_DrawPanel* panel, wxDC* DC,
         block->Draw( panel, DC, block->m_MoveVector, g_XorMode, block->m_Color );
         for( unsigned ii = 0; ii < block->GetCount(); ii++ )
         {
-            schitem = (SCH_ITEM*) block->m_ItemsSelection.GetItemData( ii );
+            schitem = (SCH_ITEM*) block->m_ItemsSelection.GetPickedItem( ii );
             DrawStructsInGhost( panel, DC, schitem, block->m_MoveVector );
         }
     }
@@ -492,7 +492,7 @@ static void DrawMovingBlockOutlines( WinEDA_DrawPanel* panel, wxDC* DC,
 
     for( unsigned ii = 0; ii < block->GetCount(); ii++ )
     {
-        schitem = (SCH_ITEM*) block->m_ItemsSelection.GetItemData( ii );
+        schitem = (SCH_ITEM*) block->m_ItemsSelection.GetPickedItem( ii );
         DrawStructsInGhost( panel, DC, schitem, block->m_MoveVector );
     }
 }
@@ -515,9 +515,9 @@ void SaveStructListForPaste( PICKED_ITEMS_LIST& aItemsList )
     for( unsigned ii = 0; ii < aItemsList.GetCount(); ii++ )
     {
         /* Make a copy of the original picked item. */
-        SCH_ITEM* DrawStructCopy = DuplicateStruct( (SCH_ITEM*) aItemsList.GetItemData( ii ) );
+        SCH_ITEM* DrawStructCopy = DuplicateStruct( (SCH_ITEM*) aItemsList.GetPickedItem( ii ) );
         DrawStructCopy->SetParent( NULL );
-        item.m_Item = DrawStructCopy;
+        item.m_PickedItem = DrawStructCopy;
         g_BlockSaveDataList.PushItem( item );
     }
 }
@@ -543,8 +543,8 @@ void WinEDA_SchematicFrame::PasteListOfItems( wxDC* DC )
     ITEM_PICKER picker( NULL, UR_NEW );
     for( unsigned ii = 0; ii < g_BlockSaveDataList.GetCount(); ii++ )
     {
-        Struct = DuplicateStruct( (SCH_ITEM*) g_BlockSaveDataList.m_ItemsSelection.GetItemData( ii ) );
-        picker.m_Item = Struct;
+        Struct = DuplicateStruct( (SCH_ITEM*) g_BlockSaveDataList.m_ItemsSelection.GetPickedItem( ii ) );
+        picker.m_PickedItem = Struct;
         picklist.PushItem( picker );
 
         // Clear annotation and init new time stamp for the new components:
@@ -600,7 +600,7 @@ static void CollectStructsToDrag( SCH_SCREEN* screen )
     // Sel .m_Flags to selected for a wire or bus in selected area if there is only one item:
     if( pickedlist->GetCount() == 1 )
     {
-        Struct = (SCH_ITEM*) pickedlist->GetItemData( 0 );
+        Struct = (SCH_ITEM*) pickedlist->GetPickedItem( 0 );
         if( Struct->Type() == DRAW_SEGMENT_STRUCT_TYPE )
             Struct->m_Flags = SELECTED;
     }
@@ -609,7 +609,7 @@ static void CollectStructsToDrag( SCH_SCREEN* screen )
     {
         for( unsigned ii = 0; ii < pickedlist->GetCount(); ii++ )
         {
-            Struct = (SCH_ITEM*)(SCH_ITEM*) pickedlist->GetItemData( ii );
+            Struct = (SCH_ITEM*)(SCH_ITEM*) pickedlist->GetPickedItem( ii );
             Struct->m_Flags = SELECTED;
         }
     }
@@ -632,7 +632,7 @@ static void CollectStructsToDrag( SCH_SCREEN* screen )
      *  de selection */
     for( unsigned ii = 0; ii < pickedlist->GetCount(); ii++ )
     {
-        Struct = (SCH_ITEM*)(SCH_ITEM*) pickedlist->GetItemData( ii );
+        Struct = (SCH_ITEM*)(SCH_ITEM*) pickedlist->GetPickedItem( ii );
         if( Struct->Type() == DRAW_SEGMENT_STRUCT_TYPE )
         {
             SegmStruct = (EDA_DrawLineStruct*) Struct;
@@ -651,7 +651,7 @@ static void CollectStructsToDrag( SCH_SCREEN* screen )
 
     for( unsigned ii = 0; ii < pickedlist->GetCount(); ii++ )
     {
-        Struct = (SCH_ITEM*)(SCH_ITEM*) pickedlist->GetItemData( ii );
+        Struct = (SCH_ITEM*)(SCH_ITEM*) pickedlist->GetPickedItem( ii );
         if( Struct->Type() == TYPE_SCH_COMPONENT )
         {
             // Add all pins of the selected component to list
@@ -712,7 +712,7 @@ static void AddPickedItem( SCH_SCREEN* screen, wxPoint position )
 
     for( unsigned ii = 0; ii < pickedlist->GetCount(); ii++ )
     {
-        Struct = (SCH_ITEM*) pickedlist->GetItemData( ii );
+        Struct = (SCH_ITEM*) pickedlist->GetPickedItem( ii );
 
         switch( Struct->Type() )
         {
@@ -737,6 +737,8 @@ static void AddPickedItem( SCH_SCREEN* screen, wxPoint position )
     Struct = screen->EEDrawList;
     while( Struct )
     {
+        picker.m_PickedItem    = Struct;
+        picker.m_PickedItemType = Struct->Type();
         switch( Struct->Type() )
         {
         case TYPE_NOT_INIT:
@@ -754,7 +756,6 @@ static void AddPickedItem( SCH_SCREEN* screen, wxPoint position )
                 break; /* Deja en liste */
             if( STRUCT->m_Pos != position )
                 break;
-            picker.m_Item = Struct;
             pickedlist->PushItem( picker );
             break;
 
@@ -767,14 +768,12 @@ static void AddPickedItem( SCH_SCREEN* screen, wxPoint position )
             {
                 Struct->m_Flags  = SELECTED | ENDPOINT | STARTPOINT;
                 Struct->m_Flags &= ~STARTPOINT;
-                picker.m_Item    = Struct;
                 pickedlist->PushItem( picker );
             }
             else if( STRUCT->m_End == position )
             {
                 Struct->m_Flags  = SELECTED | ENDPOINT | STARTPOINT;
                 Struct->m_Flags &= ~ENDPOINT;
-                picker.m_Item    = Struct;
                 pickedlist->PushItem( picker );
             }
             break;
@@ -793,7 +792,6 @@ static void AddPickedItem( SCH_SCREEN* screen, wxPoint position )
             if( STRUCT->m_Pos != position )
                 break;
             Struct->m_Flags |= SELECTED;
-            picker.m_Item    = Struct;
             pickedlist->PushItem( picker );
             break;
 
@@ -806,7 +804,6 @@ static void AddPickedItem( SCH_SCREEN* screen, wxPoint position )
             if( STRUCT->m_Pos != position )
                 break;
             Struct->m_Flags |= SELECTED;
-            picker.m_Item    = Struct;
             pickedlist->PushItem( picker );
             break;
 
@@ -823,7 +820,6 @@ static void AddPickedItem( SCH_SCREEN* screen, wxPoint position )
             if( STRUCT->m_Pos != position )
                 break;
             Struct->m_Flags |= SELECTED;
-            picker.m_Item    = Struct;
             pickedlist->PushItem( picker );
             break;
 
@@ -835,7 +831,6 @@ static void AddPickedItem( SCH_SCREEN* screen, wxPoint position )
             if( STRUCT->m_Pos != position )
                 break;
             Struct->m_Flags |= SELECTED;
-            picker.m_Item    = Struct;
             pickedlist->PushItem( picker );
             break;
 
diff --git a/eeschema/delete.cpp b/eeschema/delete.cpp
index 6b210aa883..bc0ab43367 100644
--- a/eeschema/delete.cpp
+++ b/eeschema/delete.cpp
@@ -149,7 +149,8 @@ void WinEDA_SchematicFrame::DeleteConnection( bool DeleteFullConnection )
         DelStruct->m_Flags = SELECTEDNODE | STRUCT_DELETED;
 
         /* Put this structure in the picked list: */
-        picker.m_Item = DelStruct;
+        picker.m_PickedItem = DelStruct;
+        picker.m_PickedItemType = DelStruct->Type();
         pickList.PushItem(picker);
 
         DelStruct  = DelStruct->Next();
@@ -237,7 +238,8 @@ void WinEDA_SchematicFrame::DeleteConnection( bool DeleteFullConnection )
             {
                 DelStruct->m_Flags |= STRUCT_DELETED;
                 /* Put this structure in the picked list: */
-                picker.m_Item = DelStruct;
+                picker.m_PickedItem = DelStruct;
+                picker.m_PickedItemType = DelStruct->Type();
                 pickList.PushItem(picker);
 
                 DelStruct  = GetScreen()->EEDrawList;
@@ -264,7 +266,8 @@ void WinEDA_SchematicFrame::DeleteConnection( bool DeleteFullConnection )
                     DelStruct->m_Flags |= STRUCT_DELETED;
 
                     /* Put this structure in the picked list: */
-                    picker.m_Item = DelStruct;
+                    picker.m_PickedItem = DelStruct;
+                    picker.m_PickedItemType = DelStruct->Type();
                     pickList.PushItem(picker);
                 }
                 #undef JUNCTION
@@ -290,7 +293,8 @@ void WinEDA_SchematicFrame::DeleteConnection( bool DeleteFullConnection )
                 DelStruct->m_Flags |= STRUCT_DELETED;
 
                 /* Put this structure in the picked list: */
-                picker.m_Item = DelStruct;
+                picker.m_PickedItem = DelStruct;
+                picker.m_PickedItemType = DelStruct->Type();
                 pickList.PushItem(picker);
             }
         }
diff --git a/eeschema/libedit_undo_redo.cpp b/eeschema/libedit_undo_redo.cpp
index 8b2f089e47..755d574398 100644
--- a/eeschema/libedit_undo_redo.cpp
+++ b/eeschema/libedit_undo_redo.cpp
@@ -39,9 +39,9 @@ void WinEDA_LibeditFrame::SaveCopyInUndoList( EDA_BaseStruct* ItemToCopy,
         while ( 1 )
         {
             wrapper = lastcmd->PopItem();
-            if ( wrapper.m_Item == NULL )
+            if ( wrapper.m_PickedItem == NULL )
                 break;      // All items are removed
-            delete wrapper.m_Item;
+            delete wrapper.m_PickedItem;
         }
         delete lastcmd;
     }
@@ -69,7 +69,7 @@ void WinEDA_LibeditFrame::GetComponentFromRedoList(wxCommandEvent& event)
     lastcmd = GetScreen()->PopCommandFromRedoList( );
 
     wrapper = lastcmd->PopItem();
-    CurrentLibEntry = (EDA_LibComponentStruct*) wrapper.m_Item;
+    CurrentLibEntry = (EDA_LibComponentStruct*) wrapper.m_PickedItem;
     if( CurrentLibEntry )
         CurrentLibEntry->SetNext( NULL );
     CurrentDrawItem = NULL;
@@ -102,7 +102,7 @@ void WinEDA_LibeditFrame::GetComponentFromUndoList(wxCommandEvent& event)
     lastcmd = GetScreen()->PopCommandFromUndoList( );
 
     wrapper = lastcmd->PopItem();
-    CurrentLibEntry = (EDA_LibComponentStruct*) wrapper.m_Item;
+    CurrentLibEntry = (EDA_LibComponentStruct*) wrapper.m_PickedItem;
 
     if( CurrentLibEntry )
         CurrentLibEntry->SetNext( NULL );
diff --git a/eeschema/locate.cpp b/eeschema/locate.cpp
index 0b8204d2ea..24c71b3448 100644
--- a/eeschema/locate.cpp
+++ b/eeschema/locate.cpp
@@ -149,7 +149,8 @@ int PickItemsInBlock( BLOCK_SELECTOR& aBlock, BASE_SCREEN* aScreen )
         if( DrawStructInBox( OrigX, OrigY, x, y, DrawStruct ) )
         {
             /* Put this structure in the picked list: */
-            picker.m_Item = DrawStruct;
+            picker.m_PickedItem = DrawStruct;
+            picker.m_PickedItemType = DrawStruct->Type();
             aBlock.PushItem(picker);
             itemcount++;
         }
diff --git a/eeschema/operations_on_items_lists.cpp b/eeschema/operations_on_items_lists.cpp
index 7651114834..4d28500056 100644
--- a/eeschema/operations_on_items_lists.cpp
+++ b/eeschema/operations_on_items_lists.cpp
@@ -29,7 +29,7 @@ void MirrorListOfItems( PICKED_ITEMS_LIST& aItemsList, wxPoint& aMirrorPoint )
 {
     for( unsigned ii = 0; ii < aItemsList.GetCount(); ii++ )
     {
-        SCH_ITEM* item = (SCH_ITEM*) aItemsList.GetItemData( ii );
+        SCH_ITEM* item = (SCH_ITEM*) aItemsList.GetPickedItem( ii );
         item->Mirror_Y( aMirrorPoint.x );      // Place it in its new position.
         item->m_Flags = 0;
     }
@@ -46,7 +46,7 @@ void MoveItemsInList( PICKED_ITEMS_LIST& aItemsList, const wxPoint aMoveVector )
 {
     for( unsigned ii = 0; ii < aItemsList.GetCount(); ii++ )
     {
-        SCH_ITEM* item = (SCH_ITEM*) aItemsList.GetItemData( ii );
+        SCH_ITEM* item = (SCH_ITEM*) aItemsList.GetPickedItem( ii );
         item->Move( aMoveVector );
     }
 }
@@ -66,8 +66,8 @@ void DeleteItemsInList( WinEDA_DrawPanel* panel, PICKED_ITEMS_LIST& aItemsList )
 
     for( unsigned ii = 0; ii < aItemsList.GetCount(); ii++ )
     {
-        SCH_ITEM* item = (SCH_ITEM*) aItemsList.GetItemData( ii );
-        itemWrapper.m_Item = item;
+        SCH_ITEM* item = (SCH_ITEM*) aItemsList.GetPickedItem( ii );
+        itemWrapper.m_PickedItem = item;
         itemWrapper.m_UndoRedoStatus = UR_DELETED;
         if( item->Type() == DRAW_HIERARCHICAL_PIN_SHEET_STRUCT_TYPE )
         {
@@ -77,7 +77,7 @@ void DeleteItemsInList( WinEDA_DrawPanel* panel, PICKED_ITEMS_LIST& aItemsList )
 #if 0
             Hierarchical_PIN_Sheet_Struct* pinlabel = (Hierarchical_PIN_Sheet_Struct*) item;
             frame->DeleteSheetLabel( false, pinlabel->m_Parent );
-            itemWrapper.m_Item = pinlabel->m_Parent;
+            itemWrapper.m_PickedItem = pinlabel->m_Parent;
             itemWrapper.m_UndoRedoStatus = UR_CHANGED;
             itemsList.PushItem( itemWrapper );
 #endif
@@ -154,9 +154,9 @@ void DuplicateItemsInList( SCH_SCREEN* screen, PICKED_ITEMS_LIST& aItemsList, co
 
     for( unsigned ii = 0; ii < aItemsList.GetCount(); ii++ )
     {
-        newitem = DuplicateStruct( (SCH_ITEM*) aItemsList.GetItemData( ii ) );
-        aItemsList.SetItem( newitem, ii );
-        aItemsList.SetItemStatus( UR_NEW, ii );
+        newitem = DuplicateStruct( (SCH_ITEM*) aItemsList.GetPickedItem( ii ) );
+        aItemsList.SetPickedItem( newitem, ii );
+        aItemsList.SetPickedItemStatus( UR_NEW, ii );
         {
             switch( newitem->Type() )
             {
diff --git a/eeschema/schematic_undo_redo.cpp b/eeschema/schematic_undo_redo.cpp
index bacc92ec30..834d19a489 100644
--- a/eeschema/schematic_undo_redo.cpp
+++ b/eeschema/schematic_undo_redo.cpp
@@ -212,12 +212,13 @@ void WinEDA_SchematicFrame::SaveCopyInUndoList( SCH_ITEM*      aItemToCopy,
     commandToUndo->m_TransformPoint = aTransformPoint;
 
     ITEM_PICKER        itemWrapper( aItemToCopy, aCommandType );
+    itemWrapper.m_PickedItemType = aItemToCopy->Type();
 
     switch( aCommandType )
     {
     case UR_CHANGED:            /* Create a copy of schematic */
         CopyOfItem = DuplicateStruct( aItemToCopy );
-        itemWrapper.m_Item = CopyOfItem;
+        itemWrapper.m_PickedItem = CopyOfItem;
         itemWrapper.m_Link = aItemToCopy;
         if ( CopyOfItem )
             commandToUndo->PushItem( itemWrapper );
@@ -268,19 +269,20 @@ void WinEDA_SchematicFrame::SaveCopyInUndoList( PICKED_ITEMS_LIST& aItemsList,
 
     for( unsigned ii = 0; ii < aItemsList.GetCount(); ii++ )
     {
-        SCH_ITEM*      ItemToCopy = (SCH_ITEM*) aItemsList.GetItemData( ii );
-        UndoRedoOpType command    = aItemsList.GetItemStatus( ii );
+        SCH_ITEM*      ItemToCopy = (SCH_ITEM*) aItemsList.GetPickedItem( ii );
+        UndoRedoOpType command    = aItemsList.GetPickedItemStatus( ii );
         if( command == UR_UNSPECIFIED )
         {
             command = aTypeCommand;
         }
-        itemWrapper.m_Item = ItemToCopy;
+        itemWrapper.m_PickedItem = ItemToCopy;
+        itemWrapper.m_PickedItemType = ItemToCopy->Type();
         itemWrapper.m_UndoRedoStatus = command;
         switch( command )
         {
         case UR_CHANGED:        /* Create a copy of schematic */
             CopyOfItem = DuplicateStruct( ItemToCopy );
-            itemWrapper.m_Item = CopyOfItem;
+            itemWrapper.m_PickedItem = CopyOfItem;
             itemWrapper.m_Link = ItemToCopy;
             if ( CopyOfItem )
                 commandToUndo->PushItem( itemWrapper );
@@ -335,7 +337,7 @@ void WinEDA_SchematicFrame::PutDataInPreviousState( PICKED_ITEMS_LIST* aList )
     for( unsigned ii = 0; ii < aList->GetCount(); ii++  )
     {
         ITEM_PICKER itemWrapper = aList->GetItemWrapper( ii );
-        item = (SCH_ITEM*) itemWrapper.m_Item;
+        item = (SCH_ITEM*) itemWrapper.m_PickedItem;
         wxASSERT( item  );
         SCH_ITEM*   image = (SCH_ITEM*) itemWrapper.m_Link;
         switch( itemWrapper.m_UndoRedoStatus )
@@ -345,13 +347,13 @@ void WinEDA_SchematicFrame::PutDataInPreviousState( PICKED_ITEMS_LIST* aList )
             break;
 
         case UR_NEW:        /* new items are deleted */
-            aList->SetItemStatus( UR_DELETED, ii );
+            aList->SetPickedItemStatus( UR_DELETED, ii );
             GetScreen()->RemoveFromDrawList( item );
             item->m_Flags = UR_DELETED;
             break;
 
         case UR_DELETED:    /* deleted items are put in EEdrawList, as new items */
-            aList->SetItemStatus( UR_NEW, ii );
+            aList->SetPickedItemStatus( UR_NEW, ii );
             item->SetNext( GetScreen()->EEDrawList );
             GetScreen()->EEDrawList = item;
             item->m_Flags = 0;
@@ -372,7 +374,7 @@ void WinEDA_SchematicFrame::PutDataInPreviousState( PICKED_ITEMS_LIST* aList )
         case UR_WIRE_IMAGE:
             /* Exchange the current wires and the old wires */
             alt_item = GetScreen()->ExtractWires( false );
-            aList->SetItem( alt_item, ii );
+            aList->SetPickedItem( alt_item, ii );
             while( item )
             {
                 SCH_ITEM* nextitem = item->Next();
@@ -496,7 +498,7 @@ void SCH_SCREEN::ClearUndoORRedoList( UNDO_REDO_CONTAINER& aList, int aItemCount
         while( 1 )
         {
             ITEM_PICKER     wrapper = curr_cmd->PopItem();
-            EDA_BaseStruct* item    = wrapper.m_Item;
+            EDA_BaseStruct* item    = wrapper.m_PickedItem;
             if( item == NULL ) // No more item in list.
                 break;
             switch( wrapper.m_UndoRedoStatus )
diff --git a/gerbview/block.cpp b/gerbview/block.cpp
index c8f55424b6..1abba5a725 100644
--- a/gerbview/block.cpp
+++ b/gerbview/block.cpp
@@ -257,7 +257,7 @@ static void DrawMovingBlockOutlines( WinEDA_DrawPanel* panel, wxDC* DC, bool era
 
 
 /************************************************/
-void WinEDA_BasePcbFrame::Block_Delete( wxDC* DC )
+void WinEDA_GerberFrame::Block_Delete( wxDC* DC )
 /************************************************/
 
 /*
@@ -302,7 +302,7 @@ void WinEDA_BasePcbFrame::Block_Delete( wxDC* DC )
 
 
 /************************************************/
-void WinEDA_BasePcbFrame::Block_Move( wxDC* DC )
+void WinEDA_GerberFrame::Block_Move( wxDC* DC )
 /************************************************/
 
 /*
@@ -366,7 +366,7 @@ void WinEDA_BasePcbFrame::Block_Move( wxDC* DC )
 
 
 /************************************************/
-void WinEDA_BasePcbFrame::Block_Mirror_X( wxDC* DC )
+void WinEDA_GerberFrame::Block_Mirror_X( wxDC* DC )
 /************************************************/
 
 /*
@@ -426,7 +426,7 @@ void WinEDA_BasePcbFrame::Block_Mirror_X( wxDC* DC )
 
 
 /**************************************************/
-void WinEDA_BasePcbFrame::Block_Duplicate( wxDC* DC )
+void WinEDA_GerberFrame::Block_Duplicate( wxDC* DC )
 /**************************************************/
 
 /*
diff --git a/gerbview/wxGerberFrame.h b/gerbview/wxGerberFrame.h
index ecaeab9626..7e7f133b48 100644
--- a/gerbview/wxGerberFrame.h
+++ b/gerbview/wxGerberFrame.h
@@ -53,6 +53,43 @@ public:
     virtual void HandleBlockPlace( wxDC* DC );
     virtual int  HandleBlockEnd( wxDC* DC );
 
+    /* Block operations: */
+    /**
+     * Function Block_Delete
+     * deletes all tracks and segments within the selected block.
+     * Defined separately in pcbnew and gerbview
+     *
+     * @param DC A device context to draw on.
+     */
+    void                     Block_Delete( wxDC* DC );
+    void                     Block_Rotate( wxDC* DC );
+    void                     Block_Invert( wxDC* DC );
+    /**
+     * Function Block_Move
+     * moves all tracks and segments within the selected block.
+     * New location is determined by the current offset from the selected block's original location.
+     * Defined separately in pcbnew and gerbview
+     *
+     * @param DC A device context to draw on.
+     */
+    void                     Block_Move( wxDC* DC );
+    /**
+     * Function Block_Mirror_X
+     * mirrors all tracks and segments within the currently selected block in the X axis.
+     *
+     * @param DC A device context to draw on.
+     */
+    void                     Block_Mirror_X( wxDC* DC );
+    /**
+     * Function Block_Duplicate
+     * copies-and-moves all tracks and segments within the selected block.
+     * New location is determined by the current offset from the selected block's original location.
+     * Defined separately in pcbnew and gerbview
+     *
+     * @param DC A device context to draw on.
+     */
+    void                     Block_Duplicate( wxDC* DC );
+
     void         InstallDrillFrame( wxCommandEvent& event );
     void         ToPostProcess( wxCommandEvent& event );
     void         Genere_HPGL( const wxString& FullFileName, int Layers );
diff --git a/include/class_undoredo_container.h b/include/class_undoredo_container.h
index 2c46e933ee..c3773f485d 100644
--- a/include/class_undoredo_container.h
+++ b/include/class_undoredo_container.h
@@ -26,6 +26,8 @@
 #define _CLASS_UNDOREDO_CONTAINER_H
 #include <vector>
 
+#include "base_struct.h"
+
 /**
  * @info Undo Redo considerations:
  * Basically we have 3 cases
@@ -65,9 +67,11 @@ class ITEM_PICKER
 {
 public:
     UndoRedoOpType  m_UndoRedoStatus;   /* type of operation to undo/redo for this item */
-    EDA_BaseStruct* m_Item;             /* Pointer on the schematic or board item that is concerned,
+    EDA_BaseStruct* m_PickedItem;       /* Pointer on the schematic or board item that is concerned (picked),
                                          *  or in undo redo commands, the copy of an edited item.
                                          */
+    KICAD_T         m_PickedItemType;   /* type of schematic or board item that is concerned
+                                         */
     EDA_BaseStruct* m_Link;             /* Pointer on an other item. Used in undo redo command
                                          * used when a duplicate exists i.e. when an item is modified,
                                          * and the copy of initial item exists (the duplicate)
@@ -76,12 +80,8 @@ public:
                                          */
 
 public:
-    ITEM_PICKER( EDA_BaseStruct* aItem = NULL, UndoRedoOpType aUndoRedoStatus = UR_UNSPECIFIED )
-    {
-        m_UndoRedoStatus = aUndoRedoStatus;
-        m_Item = aItem;
-        m_Link = NULL;
-    }
+    ITEM_PICKER( EDA_BaseStruct* aItem = NULL,
+        UndoRedoOpType aUndoRedoStatus = UR_UNSPECIFIED );
 };
 
 /* Class PICKED_ITEMS_LIST
@@ -121,15 +121,70 @@ public:
     }
 
 
+    /** function GetItemWrapper
+     * @return the picker of a picked item
+     * @param aIdx = index of the picker in the picked list
+     * if this picker does not exist, a picker is returned,
+     * with its members set to 0 or NULL
+     */
     ITEM_PICKER     GetItemWrapper( unsigned int aIdx );
-    EDA_BaseStruct* GetItemData( unsigned int aIdx );
-    EDA_BaseStruct* GetImage( unsigned int aIdx );
-    UndoRedoOpType  GetItemStatus( unsigned int aIdx );
-    bool            SetItem( EDA_BaseStruct* aItem, unsigned aIdx );
-    bool            SetItem( EDA_BaseStruct* aItem, UndoRedoOpType aStatus, unsigned aIdx );
-    bool            SetLink( EDA_BaseStruct* aItem, unsigned aIdx );
-    bool            SetItemStatus( UndoRedoOpType aStatus, unsigned aIdx );
-    bool            RemoveItem( unsigned aIdx );
+
+    /** function GetPickedItem
+     * @return a pointer to the picked item
+     * @param aIdx = index of the picked item in the picked list
+     */
+    EDA_BaseStruct* GetPickedItem( unsigned int aIdx );
+
+    /** function GetLink
+     * @return link of the picked item, or null if does not exist
+     * @param aIdx = index of the picked item in the picked list
+     */
+    EDA_BaseStruct* GetLink( unsigned int aIdx );
+
+    /** function GetPickedItemStatus
+     * @return the type of undo/redo opertaion associated to the picked item,
+     *   or UR_UNSPECIFIED if does not exist
+     * @param aIdx = index of the picked item in the picked list
+     */
+    UndoRedoOpType  GetPickedItemStatus( unsigned int aIdx );
+
+    /** function SetPickedItem
+     * @param aItem = a pointer to the item to pick
+     * @param aIdx = index of the picker in the picked list
+     * @return true if the pixker exists, or false if does not exist
+     */
+    bool            SetPickedItem( EDA_BaseStruct* aItem, unsigned aIdx );
+
+    /** function SetPickedItem
+     * @param aItem = a pointer to the item to pick
+     * @param aStatus = the type of undo/redo operation associated to the item to pick
+     * @param aIdx = index of the picker in the picked list
+     * @return true if the pixker exists, or false if does not exist
+     */
+    bool            SetPickedItem( EDA_BaseStruct* aItem, UndoRedoOpType aStatus, unsigned aIdx );
+
+    /** function SetLink
+     * Set the link associated to a given picked item
+     * @param aLink = the link to the item associated to the picked item
+     * @param aIdx = index of the picker in the picked list
+     * @return true if the pixker exists, or false if does not exist
+     */
+    bool            SetLink( EDA_BaseStruct* aLink, unsigned aIdx );
+
+    /** function SetPickedItemStatus
+     * Set the the type of undo/redo operation for a given picked item
+     * @param aStatus = the type of undo/redo operation associated to the picked item
+     * @param aIdx = index of the picker in the picked list
+     * @return true if the picker exists, or false if does not exist
+     */
+    bool            SetPickedItemStatus( UndoRedoOpType aStatus, unsigned aIdx );
+
+    /** function RemovePickedItem
+     * remùove one entry (one picker) from the list of picked items
+     * @param aIdx = index of the picker in the picked list
+     * @return true if ok, or false if did not exist
+     */
+    bool            RemovePickedItem( unsigned aIdx );
 
     /** Function CopyList
      * copy all data from aSource
diff --git a/include/wxBasePcbFrame.h b/include/wxBasePcbFrame.h
index 1c646df7e8..77286fe535 100644
--- a/include/wxBasePcbFrame.h
+++ b/include/wxBasePcbFrame.h
@@ -310,43 +310,6 @@ public:
     virtual void        SaveCopyInUndoList( BOARD_ITEM* aItemToCopy, UndoRedoOpType aTypeCommand,
                         const wxPoint& aTransformPoint = wxPoint(0,0) ) = 0;
 
-    /* Block operations: */
-    /**
-     * Function Block_Delete
-     * deletes all tracks and segments within the selected block.
-     * Defined separately in pcbnew and gerbview
-     *
-     * @param DC A device context to draw on.
-     */
-    void                     Block_Delete( wxDC* DC );
-    void                     Block_Rotate( wxDC* DC );
-    void                     Block_Invert( wxDC* DC );
-    /**
-     * Function Block_Move
-     * moves all tracks and segments within the selected block.
-     * New location is determined by the current offset from the selected block's original location.
-     * Defined separately in pcbnew and gerbview
-     *
-     * @param DC A device context to draw on.
-     */
-    void                     Block_Move( wxDC* DC );
-    /**
-     * Function Block_Mirror_X
-     * mirrors all tracks and segments within the currently selected block in the X axis.
-     *
-     * @param DC A device context to draw on.
-     */
-    void                     Block_Mirror_X( wxDC* DC );
-    /**
-     * Function Block_Duplicate
-     * copies-and-moves all tracks and segments within the selected block.
-     * New location is determined by the current offset from the selected block's original location.
-     * Defined separately in pcbnew and gerbview
-     *
-     * @param DC A device context to draw on.
-     */
-     void                     Block_Duplicate( wxDC* DC );
-
 
     // layerhandling:
     // (See pcbnew/sel_layer.cpp for description of why null_layer parameter is provided)
diff --git a/include/wxPcbStruct.h b/include/wxPcbStruct.h
index c4d397ce10..929497af20 100644
--- a/include/wxPcbStruct.h
+++ b/include/wxPcbStruct.h
@@ -165,6 +165,44 @@ public:
     void             HandleBlockPlace( wxDC* DC );
     int              HandleBlockEnd( wxDC* DC );
 
+    /* Block operations: */
+    /**
+     * Function Block_Delete
+     * deletes all tracks and segments within the selected block.
+     * Defined separately in pcbnew and gerbview
+     *
+     * @param DC A device context to draw on.
+     */
+    void                     Block_Delete( wxDC* DC );
+    void                     Block_Rotate( wxDC* DC );
+    void                     Block_Invert( wxDC* DC );
+    /**
+     * Function Block_Move
+     * moves all tracks and segments within the selected block.
+     * New location is determined by the current offset from the selected block's original location.
+     * Defined separately in pcbnew and gerbview
+     *
+     * @param DC A device context to draw on.
+     */
+    void                     Block_Move( wxDC* DC );
+    /**
+     * Function Block_Mirror_X
+     * mirrors all tracks and segments within the currently selected block in the X axis.
+     *
+     * @param DC A device context to draw on.
+     */
+    void                     Block_Mirror_X( wxDC* DC );
+    /**
+     * Function Block_Duplicate
+     * copies-and-moves all tracks and segments within the selected block.
+     * New location is determined by the current offset from the selected block's original location.
+     * Defined separately in pcbnew and gerbview
+     *
+     * @param DC A device context to draw on.
+     */
+     void                     Block_Duplicate( wxDC* DC );
+
+
     void             SetToolbars();
     void             Process_Settings( wxCommandEvent& event );
     void             InstallPcbOptionsFrame( const wxPoint& pos, wxDC* DC, int id );
diff --git a/pcbnew/block.cpp b/pcbnew/block.cpp
index 91faab1f3c..a54eea8686 100644
--- a/pcbnew/block.cpp
+++ b/pcbnew/block.cpp
@@ -432,9 +432,8 @@ static void DrawMovingBlockOutlines( WinEDA_DrawPanel* panel, wxDC* DC, bool era
 
 
 /************************************************/
-void WinEDA_BasePcbFrame::Block_Delete( wxDC* DC )
+void WinEDA_PcbFrame::Block_Delete( wxDC* DC )
 /************************************************/
-
 /*
  *  routine d'effacement du block deja selectionne
  */
@@ -449,6 +448,9 @@ void WinEDA_BasePcbFrame::Block_Delete( wxDC* DC )
     GetScreen()->m_BlockLocate.Normalize();
     SetCurItem( NULL );
 
+    PICKED_ITEMS_LIST      itemsList;
+    ITEM_PICKER            picker(NULL,UR_DELETED);
+
     /* Effacement des modules */
     if( Block_Include_Modules )
     {
@@ -460,13 +462,16 @@ void WinEDA_BasePcbFrame::Block_Delete( wxDC* DC )
             if( module->HitTest( GetScreen()->m_BlockLocate ) )
             {
                 module->m_Flags = 0;
-                module->DeleteStructure();
+                module->UnLink();
                 m_Pcb->m_Status_Pcb = 0;
+                picker.m_PickedItem = module;
+                picker.m_PickedItemType = module->Type();
+                itemsList.PushItem(picker);
             }
         }
     }
 
-    /* Effacement des Pistes */
+    /* Remove tracks and vias */
     if( Block_Include_Tracks )
     {
         TRACK* pt_segm;
@@ -476,13 +481,16 @@ void WinEDA_BasePcbFrame::Block_Delete( wxDC* DC )
             NextS = pt_segm->Next();
             if( pt_segm->HitTest( GetScreen()->m_BlockLocate ) )
             {
-                /* la piste est ici bonne a etre efface */
-                pt_segm->DeleteStructure();
+                /* This track is in bloc: remove it */
+                pt_segm->UnLink();
+                picker.m_PickedItem = pt_segm;
+                picker.m_PickedItemType = pt_segm->Type();
+                itemsList.PushItem(picker);
             }
         }
     }
 
-    /* Effacement des Elements De Dessin */
+    /* Remove graphic items */
     masque_layer = EDGE_LAYER;
     if( Block_Include_Draw_Items )
         masque_layer = ALL_LAYERS;
@@ -494,7 +502,7 @@ void WinEDA_BasePcbFrame::Block_Delete( wxDC* DC )
     for( ; PtStruct != NULL; PtStruct = NextS )
     {
         NextS = PtStruct->Next();
-
+        bool remove_me = false;
         switch( PtStruct->Type() )
         {
         case TYPE_DRAWSEGMENT:
@@ -502,10 +510,7 @@ void WinEDA_BasePcbFrame::Block_Delete( wxDC* DC )
                 break;
             if( ! PtStruct->HitTest( GetScreen()->m_BlockLocate ) )
                 break;
-
-            /* l'element est ici bon a etre efface */
-            PtStruct->Draw( DrawPanel, DC, GR_XOR );
-            PtStruct->DeleteStructure();
+            remove_me = true; // This item is in bloc: remove it
             break;
 
         case TYPE_TEXTE:
@@ -513,10 +518,7 @@ void WinEDA_BasePcbFrame::Block_Delete( wxDC* DC )
                 break;
             if( ! PtStruct->HitTest( GetScreen()->m_BlockLocate ) )
                 break;
-            /* le texte est ici bon a etre efface */
-            PtStruct->Draw( DrawPanel, DC, GR_XOR );
-            /* Suppression du texte en Memoire*/
-            PtStruct->DeleteStructure();
+            remove_me = true; // This item is in bloc: remove it
             break;
 
         case TYPE_MIRE:
@@ -524,8 +526,7 @@ void WinEDA_BasePcbFrame::Block_Delete( wxDC* DC )
                 break;
             if( ! PtStruct->HitTest( GetScreen()->m_BlockLocate ) )
                 break;
-            /* l'element est ici bon a etre efface */
-            PtStruct->DeleteStructure();
+            remove_me = true; // This item is in bloc: remove it
             break;
 
         case TYPE_COTATION:
@@ -533,12 +534,20 @@ void WinEDA_BasePcbFrame::Block_Delete( wxDC* DC )
                 break;
             if( ! PtStruct->HitTest( GetScreen()->m_BlockLocate ) )
                 break;
-            PtStruct->DeleteStructure();
+            remove_me = true; // This item is in bloc: remove it
             break;
 
         default:
             break;
         }
+
+        if ( remove_me )
+        {
+            PtStruct->UnLink();
+            picker.m_PickedItem = PtStruct;
+            picker.m_PickedItemType = PtStruct->Type();
+            itemsList.PushItem(picker);
+        }
     }
 
     /* Effacement des Zones */
@@ -552,7 +561,10 @@ void WinEDA_BasePcbFrame::Block_Delete( wxDC* DC )
             NextSegZ = pt_segm->Next();
             if( pt_segm->HitTest( GetScreen()->m_BlockLocate ) )
             {
-                pt_segm->DeleteStructure();
+                pt_segm->UnLink();
+                picker.m_PickedItem = PtStruct;
+                picker.m_PickedItemType = PtStruct->Type();
+                itemsList.PushItem(picker);
             }
         }
 
@@ -560,19 +572,25 @@ void WinEDA_BasePcbFrame::Block_Delete( wxDC* DC )
         {
             if( m_Pcb->GetArea(ii)->HitTest( GetScreen()->m_BlockLocate ) )
             {
-                m_Pcb->Delete(m_Pcb->GetArea(ii));
+                BOARD_ITEM* zone_c = m_Pcb->Remove(m_Pcb->GetArea(ii));
                 ii--;	// because the current data was removed, ii points actually the next data
+                picker.m_PickedItem = zone_c;
+                picker.m_PickedItemType = zone_c->Type();
+                itemsList.PushItem(picker);
             }
         }
     }
 
+    if ( itemsList.GetCount() )
+        SaveCopyInUndoList( itemsList, UR_DELETED );
+
     DrawPanel->Refresh( TRUE );
     Compile_Ratsnest( DC, TRUE );
 }
 
 
 /****************************************************/
-void WinEDA_BasePcbFrame::Block_Rotate( wxDC* DC )
+void WinEDA_PcbFrame::Block_Rotate( wxDC* DC )
 /****************************************************/
 
 /**
@@ -732,7 +750,7 @@ void WinEDA_BasePcbFrame::Block_Rotate( wxDC* DC )
 
 
 /*****************************************************/
-void WinEDA_BasePcbFrame::Block_Invert( wxDC* DC )
+void WinEDA_PcbFrame::Block_Invert( wxDC* DC )
 /*****************************************************/
 
 /*
@@ -919,7 +937,7 @@ void WinEDA_BasePcbFrame::Block_Invert( wxDC* DC )
 
 
 /************************************************/
-void WinEDA_BasePcbFrame::Block_Move( wxDC* DC )
+void WinEDA_PcbFrame::Block_Move( wxDC* DC )
 /************************************************/
 
 /*
@@ -1064,7 +1082,7 @@ void WinEDA_BasePcbFrame::Block_Move( wxDC* DC )
 
 
 /**************************************************/
-void WinEDA_BasePcbFrame::Block_Duplicate( wxDC* DC )
+void WinEDA_PcbFrame::Block_Duplicate( wxDC* DC )
 /**************************************************/
 
 /*
diff --git a/pcbnew/board_undo_redo.cpp b/pcbnew/board_undo_redo.cpp
index a512da4f75..bcf60911d3 100644
--- a/pcbnew/board_undo_redo.cpp
+++ b/pcbnew/board_undo_redo.cpp
@@ -59,6 +59,47 @@
  *
  */
 
+/** function TestForExistingItem
+ * test if aItem exists somewhere in lists of items
+ * This is a function unsed by PutDataInPreviousState to be sure an item was not deleted
+ * since an undo or redo.
+ * This could be possible:
+ *   - if a call to SaveCopyInUndoList was forgotten in pcbnew
+ *   - in zones outlines, when a change in one zone merges this zone with an other
+ * This function avoids a pcbnew crash
+ * @param aBoard = board to test
+ * @param aItem = item to find
+ */
+static bool TestForExistingItem( BOARD * aPcb, BOARD_ITEM * aItem )
+{
+    BOARD_ITEM *item;
+    // search in tracks:
+    for( item = aPcb->m_Track; item != NULL; item = item->Next() )
+        if (item == aItem )
+            return true;
+
+    // search in modules:
+    for( item = aPcb->m_Modules; item != NULL; item = item->Next() )
+        if (item == aItem )
+            return true;
+
+    // Search in drawings
+    for( item = aPcb->m_Drawings; item != NULL; item = item->Next() )
+        if (item == aItem )
+            return true;
+
+    // Search in zones outlines
+    for ( int ii = 0; ii < aPcb->GetAreaCount(); ii++ )
+        if( aPcb->GetArea(ii) == aItem )
+            return true;
+
+    // search in zones segm:
+    for( item = aPcb->m_Zone; item != NULL; item = item->Next() )
+        if (item == aItem )
+            return true;
+
+    return false;
+}
 
 /**************************************************************/
 void SwapData( EDA_BaseStruct* aItem, EDA_BaseStruct* aImage )
@@ -148,12 +189,13 @@ void WinEDA_PcbFrame::SaveCopyInUndoList( BOARD_ITEM*    aItemToCopy,
     commandToUndo->m_TransformPoint = aTransformPoint;
 
     ITEM_PICKER itemWrapper( aItemToCopy, aCommandType );
+    itemWrapper.m_PickedItemType = aItemToCopy->Type();
 
     switch( aCommandType )
     {
     case UR_CHANGED:            /* Create a copy of schematic */
         CopyOfItem = DuplicateStruct( aItemToCopy );
-        itemWrapper.m_Item = CopyOfItem;
+        itemWrapper.m_PickedItem = CopyOfItem;
         itemWrapper.m_Link = aItemToCopy;
         if( CopyOfItem )
             commandToUndo->PushItem( itemWrapper );
@@ -204,20 +246,21 @@ void WinEDA_PcbFrame::SaveCopyInUndoList( PICKED_ITEMS_LIST& aItemsList,
 
     for( unsigned ii = 0; ii < aItemsList.GetCount(); ii++ )
     {
-        BOARD_ITEM*    ItemToCopy = (BOARD_ITEM*) aItemsList.GetItemData( ii );
-        UndoRedoOpType command    = aItemsList.GetItemStatus( ii );
+        BOARD_ITEM*    ItemToCopy = (BOARD_ITEM*) aItemsList.GetPickedItem( ii );
+        UndoRedoOpType command    = aItemsList.GetPickedItemStatus( ii );
         if( command == UR_UNSPECIFIED )
         {
             command = aTypeCommand;
         }
         wxASSERT( ItemToCopy );
-        itemWrapper.m_Item = ItemToCopy;
+        itemWrapper.m_PickedItem = ItemToCopy;
+        itemWrapper.m_PickedItemType = ItemToCopy->Type();
         itemWrapper.m_UndoRedoStatus = command;
         switch( command )
         {
         case UR_CHANGED:        /* Create a copy of schematic */
             CopyOfItem = DuplicateStruct( ItemToCopy );
-            itemWrapper.m_Item = CopyOfItem;
+            itemWrapper.m_PickedItem = CopyOfItem;
             itemWrapper.m_Link = ItemToCopy;
             if( CopyOfItem )
                 commandToUndo->PushItem( itemWrapper );
@@ -267,13 +310,26 @@ void WinEDA_PcbFrame::PutDataInPreviousState( PICKED_ITEMS_LIST* aList )
 {
     BOARD_ITEM* item;
     bool        as_moved = false;
+    bool        not_found = false;
 
     for( unsigned ii = 0; ii < aList->GetCount(); ii++  )
     {
         ITEM_PICKER itemWrapper = aList->GetItemWrapper( ii );
-        item = (BOARD_ITEM*) itemWrapper.m_Item;
+        item = (BOARD_ITEM*) itemWrapper.m_PickedItem;
         wxASSERT( item );
         BOARD_ITEM* image = (BOARD_ITEM*) itemWrapper.m_Link;
+        if( itemWrapper.m_UndoRedoStatus != UR_DELETED )
+        {
+            if( ! TestForExistingItem( GetBoard(), item ) )
+            {
+                // Remove this non existant item
+                aList->RemovePickedItem( ii );
+                ii--;       // the current item was removed, ii points now the next item
+                            // whe must decrement it because it will be incremented
+                not_found = true;
+                continue;
+            }
+        }
         switch( itemWrapper.m_UndoRedoStatus )
         {
         case UR_CHANGED:    /* Exchange old and new data for each item */
@@ -281,13 +337,13 @@ void WinEDA_PcbFrame::PutDataInPreviousState( PICKED_ITEMS_LIST* aList )
             break;
 
         case UR_NEW:        /* new items are deleted */
-            aList->SetItemStatus( UR_DELETED, ii );
+            aList->SetPickedItemStatus( UR_DELETED, ii );
             GetBoard()->Remove( item );
             item->m_Flags = UR_DELETED;
             break;
 
         case UR_DELETED:    /* deleted items are put in List, as new items */
-            aList->SetItemStatus( UR_NEW, ii );
+            aList->SetPickedItemStatus( UR_NEW, ii );
             GetBoard()->Add( item );
             item->m_Flags = 0;
             break;
@@ -315,6 +371,9 @@ void WinEDA_PcbFrame::PutDataInPreviousState( PICKED_ITEMS_LIST* aList )
         }
     }
 
+    if( not_found )
+        wxMessageBox(wxT("Incomplete undo/redo command: item not found" ) );
+
     // Undo for move transform needs to change the general move vector:
     if( as_moved )
         aList->m_TransformPoint = -aList->m_TransformPoint;
@@ -412,7 +471,7 @@ void PCB_SCREEN::ClearUndoORRedoList( UNDO_REDO_CONTAINER& aList, int aItemCount
         while( 1 )
         {
             ITEM_PICKER     wrapper = curr_cmd->PopItem();
-            EDA_BaseStruct* item    = wrapper.m_Item;
+            EDA_BaseStruct* item    = wrapper.m_PickedItem;
             if( item == NULL ) // No more item in list.
                 break;
             switch( wrapper.m_UndoRedoStatus )
diff --git a/pcbnew/deltrack.cpp b/pcbnew/deltrack.cpp
index 96ff075bf4..8234724ba9 100644
--- a/pcbnew/deltrack.cpp
+++ b/pcbnew/deltrack.cpp
@@ -165,7 +165,8 @@ void WinEDA_PcbFrame::Delete_net( wxDC* DC, TRACK* aTrack )
         GetBoard()->m_Track.Remove( segm );
         // redraw the area where the track was
         DrawPanel->PostDirtyRect( segm->GetBoundingBox() );
-        picker.m_Item = segm;
+        picker.m_PickedItem = segm;
+        picker.m_PickedItemType = segm->Type();
         itemsList.PushItem(picker);
     }
 
@@ -214,7 +215,8 @@ void WinEDA_PcbFrame::Remove_One_Track( wxDC* DC, TRACK* pt_segm )
         GetBoard()->m_Track.Remove( tracksegment );
         // redraw the area where the track was
         DrawPanel->PostDirtyRect( tracksegment->GetBoundingBox() );
-        picker.m_Item = tracksegment;
+        picker.m_PickedItem = tracksegment;
+        picker.m_PickedItemType = tracksegment->Type();
         itemsList.PushItem(picker);
     }
 
diff --git a/pcbnew/modedit_undo_redo.cpp b/pcbnew/modedit_undo_redo.cpp
index a1de7b9a11..aa3210582d 100644
--- a/pcbnew/modedit_undo_redo.cpp
+++ b/pcbnew/modedit_undo_redo.cpp
@@ -41,9 +41,9 @@ void WinEDA_ModuleEditFrame::SaveCopyInUndoList( BOARD_ITEM* ItemToCopy,
         while ( 1 )
         {
             wrapper = lastcmd->PopItem();
-            if ( wrapper.m_Item == NULL )
+            if ( wrapper.m_PickedItem == NULL )
                 break;      // All items are removed
-            delete wrapper.m_Item;
+            delete wrapper.m_PickedItem;
         }
         delete lastcmd;
     }
@@ -71,7 +71,7 @@ void WinEDA_ModuleEditFrame::GetComponentFromRedoList(wxCommandEvent& event)
 
     wrapper = lastcmd->PopItem();
 
-    GetBoard()->Add( (MODULE*)  wrapper.m_Item );
+    GetBoard()->Add( (MODULE*) wrapper.m_PickedItem );
 
     SetCurItem( NULL );;
     GetScreen()->SetModify();
@@ -102,8 +102,8 @@ void WinEDA_ModuleEditFrame::GetComponentFromUndoList(wxCommandEvent& event)
 
     wrapper = lastcmd->PopItem();
 
-    if( wrapper.m_Item )
-        GetBoard()->Add( (MODULE*) wrapper.m_Item, ADD_APPEND );
+    if( wrapper.m_PickedItem )
+        GetBoard()->Add( (MODULE*) wrapper.m_PickedItem, ADD_APPEND );
 
 
     GetScreen()->SetModify();
diff --git a/pcbnew/zones_by_polygon.cpp b/pcbnew/zones_by_polygon.cpp
index eb518cf066..e0042ec28c 100644
--- a/pcbnew/zones_by_polygon.cpp
+++ b/pcbnew/zones_by_polygon.cpp
@@ -829,8 +829,11 @@ void WinEDA_PcbFrame::Delete_Zone_Contour( wxDC* DC, ZONE_CONTAINER* zone_contai
 
     Delete_Zone_Fill( DC, NULL, zone_container->m_TimeStamp );  // Remove fill segments
 
-    if( ncont == 0 )                                            // This is the main outline: remove all
-        GetBoard()->Delete( zone_container );
+    if( ncont == 0 )    // This is the main outline: remove all
+    {
+        SaveCopyInUndoList( zone_container, UR_DELETED );
+        GetBoard()->Remove( zone_container );
+    }
 
     else
     {