I have two listboxes. Listbox1 is a multiselect listbox. I want to be able to copy the selected items from listbox1 to listbox2 without creating any duplicates in listbox 2. I tried adding the items from both boxes to a collection then repopulating listbox2 with the collection, but for some reason I still get duplicat info. I thought collections wouldn't allow duplicate data? Any help would be greatly appreciated.