klmiura wrote:
{=SUM(('Aug 08'!$M$10:$M$438=Tina!A7)*('Aug 08'!$N$10:$N$438))}

I have the above formula in (Worksheet Tina) and I want to look up the
information in Column A of that worksheet to match information in (Worksheet
Aug 08) Column M and if the information matches to return the value in Column
N. I am not sure what I have done incorrectly can you please assist me.

That looks like it should work. Are you pressing Ctrl+Shift+Enter to
commit the formula?

BTW SUMIF will work here, no array needed:

=SUMIF('Aug 08'!$M$10:$M$438,Tina!A7,'Aug 08'!$N$10:$N$438)