Yes thanks, it put me on the right track. I was trying to solve it in the same way as finding out which row the mouse is over; using Windows e.X and e.Y and trying to use GetContext.

In fact all I wanted was to be enable the user to scroll the UltraGrid if needed whilst in DragDrop mode. It's easier than I thought.

private void ultraGrid_DragOver(object sender, DragEventsArgs e)
{
  UltraGrid myGrid = sender as UltraGrid;

  UIElement myElement = =myGrid.DisplayLayout.UIElement.ElementFromPoint(myGrid.PointToClient(new Point(e.X, e.Y)));

  if (myElement is ScrollArrowUIElement)
  {
    ScrollArrowUIElement arrow = myElement as ScrollArrowUIElement;
    arrow.PerformClick();
  }
}