Is there a select all button?
I think you'll need some code, but since listbox controls are really forms stuff, forum702 is probabley the more correct forum.
Anyway, somthing like this perhaps?
[tt]
dim lngCount as long
dim lst as listbox
set lst = me.controls("lstNameOfYourListBoxControl")
for lngCount = 0 to lst.listcount - 1
lst.selected(lngCount) = true
next lngCount
set lst = nothing[/tt]
Roy-Vidar