One way using Conditional Formatting, with the two lists in columns A and B,
in column A use CF, Formula is
=COUNTIF($B$1:$B$5000,A1)0
and in column B
=COUNTIF($A$1:$A$5000,B1)0
and set the formatting to turn the cell red or whatever,
Regards,
Alan.
"srain001" wrote in message
...
Hi,

I'm looking for a way to compare two lists (they're quite extensive) and
highlight the matches. Is there a formula for this?

thanx

S.