After you transfer the item, remove it from the first listbox.

Saved from a previous post. It may give you an idea you can use...

Are these controls on a UserForm on directly on a worksheet?

If it's on a userform, then you can read this:
http://groups.google.com/groups?selm...BDD4%40msn.com

If they're on a worksheet, then I used controls from the Control Toolbox
toolbar. I put 4 commandbuttons and two listboxes on the worksheet. Then I
named the Commandbuttons:

BTN_moveAllLeft
BTN_moveAllRight
BTN_MoveSelectedLeft
BTN_MoveSelectedRight

Right click on the worksheet tab and select view code. Paste this in:

Option Explicit
Private Sub BTN_moveAllLeft_Click()

Dim iCtr As Long

For iCtr = 0 To Me.ListBox2.ListCount - 1
Me.ListBox1.AddItem Me.ListBox2.List(iCtr)
Next iCtr

Me.ListBox2.Clear
End Sub
Private Sub BTN_moveAllRight_Click()

Dim iCtr As Long

For iCtr = 0 To Me.ListBox1.ListCount - 1
Me.ListBox2.AddItem Me.ListBox1.List(iCtr)
Next iCtr

Me.ListBox1.Clear
End Sub
Private Sub BTN_MoveSelectedLeft_Click()

Dim iCtr As Long

For iCtr = 0 To Me.ListBox2.ListCount - 1
If Me.ListBox2.Selected(iCtr) = True Then
Me.ListBox1.AddItem Me.ListBox2.List(iCtr)
End If
Next iCtr

For iCtr = Me.ListBox2.ListCount - 1 To 0 Step -1
If Me.ListBox2.Selected(iCtr) = True Then
Me.ListBox2.RemoveItem iCtr
End If
Next iCtr

End Sub
Private Sub BTN_MoveSelectedRight_Click()

Dim iCtr As Long

For iCtr = 0 To Me.ListBox1.ListCount - 1
If Me.ListBox1.Selected(iCtr) = True Then
Me.ListBox2.AddItem Me.ListBox1.List(iCtr)
End If
Next iCtr

For iCtr = Me.ListBox1.ListCount - 1 To 0 Step -1
If Me.ListBox1.Selected(iCtr) = True Then
Me.ListBox1.RemoveItem iCtr
End If
Next iCtr

End Sub
Private Sub Worksheet_Activate()

Dim myCell As Range

Me.ListBox1.Clear
Me.ListBox2.Clear
With Me.ListBox1

.LinkedCell = ""
.ListFillRange = ""

For Each myCell In Me.Range("g7:g19").Cells
If Trim(myCell) < "" Then
.AddItem myCell.Value
End If
Next myCell

End With

Me.ListBox1.MultiSelect = fmMultiSelectMulti
Me.ListBox2.MultiSelect = fmMultiSelectMulti

End Sub

The bad news is I wasn't sure when to populate the listbox. I chose to do it
when you activated the worksheet. I don't think you'd want this--if you click
off the sheet and come back, then the listboxes are reset.

Maybe have it populated when the workbook opens????

LuisE wrote:

I have two list boxes (multiselection).
I,m transferrig the selection from listbox1 into listbox2.
How can I prevent the user from transferring an item twice???

Thanks in advance

--

Dave Peterson