<font color=green>' im Modul</font>
Public lngIDCount As Long

<font color=green>' im Child-Form</font>
Public ID As Long
Private Sub Form_Load()
  lngIDCount = lngIDCount + 1
  ID = lngIDCount
End Sub

<font color=green>' im MDI-Form</font>
Private Sub mnuNeu_Click()
  Dim fChild As New frmChild
  fChild.Show
End Sub

Sub ChildActivate(ByVal ID As Long)
  Dim frm As Form
 
  For Each frm In Forms
    If frm.MDIChild = True Then
      If frm.ID = ID Then 
        frm.Show
        frm.SetFocus
        Exit For
      End If
    End If
  Next
End Sub

ChildActivate 5