use VLOOKUP or a combination of INDEX/MATCH against both lists e.g.
Against data items in list 1
=if(ISNA(vlookup(A2,List2,1,false)),"Not In List 2","")
Against data items in list 2
=if(ISNA(vlookup(A2,List1,1,false)),"Not In List 1","")
Where "List1" & "List2" are valid range references in your workbooks
Rgds, Geoff
We could learn a lot from crayons. Some are sharp, some are pretty and some are dull. Some have weird names and all are different colours but they all live in the same box.
Please read FAQ222-2244 before you ask a question