Working With Model Items and Diagrams > Working with diagrams > Editing diagrams > Moving items on a diagram
  
Moving items on a diagram
1. Select the items you want to move.
2. Drag the items to the required position, or use the keyboard cursor keys to move the selected items.
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You can move child items to other parent items, such as Attributes and Operations of a Class.
You can undo actions that you have performed on diagrams.
You can snap items to the grid. You can temporarily disable snap to grid while moving items by pressing the Alt or Shift key.