Use the Random Number to set the Listboxes ListIndex Property, eg.
Code:
Private Sub Command1_Click()
    Randomize Timer
    List1.ListIndex = Int(Rnd * 19)
End Sub

Private Sub Form_Load()
    Dim iIndex As Integer
    For iIndex = 1 To 20
        List1.AddItem "Item " & iIndex
    Next
End Sub
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Aaron Young
Analyst Programmer
[email protected]
[email protected]