Salut CV0808,
quelque chose comme ceci?
Private Sub Worksheet_Change(ByVal Target As Range)
'
Application.EnableEvents = False
'
If Target.Column = 3 Then Cells(Target.Row, "G").Value = IIf(Trim(Target.Value) = "Client", "Contact", "Dossier")
'
Application.EnableEvents = True
'
End Sub
A+