>How can I programatically de-select a List item(so highlighted background color returns to unselected color).
>
>What I have is two listboxes. The second list box behavior is based on first. I need the second list box to revert to unsselected state if first list box selection is changed.

First, set the MultiSelect property to .T.. Then use the listbox.Selected collection to select and unselect the various items.

thisform.listbox.Selected( thisform.Listbox.ListIndex ) = .F.