=MAX(IF(A1:A100="po12345",C1:C100))

which is an array formula, committed with Ctrl-Shift-Enter

--

HTH

RP
(remove nothere from the email address if mailing direct)


"ChristinaC" wrote in message
...
Can someone help me with this one. I have a spreadsheet with a list of
Purchase orders that have more than one line. Eg

Po No Line Date
no
po12345 1 18/02/2004
po12345 2 05/04/2005
po12345 3 16/02/2003
po12345 4 06/02/2004
po12346 1 09/02/2005 etc.....

Can someone show me what code I need to use to find the latest date in the
third column against each po number. Hope this makes sense.