Code:
Private Declare Function SetWindowPos Lib "user32" (ByVal hwnd As Long, ByVal hWndInsertAfter As Long, ByVal x As Long, ByVal y As Long, ByVal cx As Long, ByVal cy As Long, ByVal wFlags As Long) As Long
Private Const HWND_TOPMOST = -1
Private Const HWND_NOTOPMOST = -2
Private Const SWP_NOMOVE = &H2
Private Const SWP_NOSIZE = &H1
Private Const FLAGS = SWP_NOMOVE Or SWP_NOSIZE
Private Sub Form_Load()

  OnTop Me, True

End Sub
Private Sub OnTop(frm As Form, TopMost As Boolean)
  
  Select Case TopMost
    Case True
      Call SetWindowPos(Me.hwnd, HWND_TOPMOST, 0, 0, 0, 0, FLAGS)
    Case False
      Call SetWindowPos(Me.hwnd, HWND_NOTOPMOST, 0, 0, 0, 0, FLAGS)
  End Select

End Sub