Hi Lindsay,

With an event macro stored into the sheet module :

Private Sub Worksheet_Change(ByVal Target As Range)
If Target.Address = "$D$8" Or Target.Address = "$D$10" _
Or Target.Address = "$L$6" Or Target.Address = "$L$8" Then
Target.Offset(0, 4) = Now
Else
Exit Sub
End If
End Sub


HTH
Cheers
Carim