"mbr" wrote:
what function would i need to do the following:
add amounts in column d if column b is between 01/07/09 and 31/07/09.

It would be best to put the dates into cells, say A1 and B1. Then:

=sumproduct((A1<=B1:B100)*(B1:B100<=B1), D1:D100)

If you do not want to put the dates into cells for some reason, replace A1
and B1 above with DATE(2009,7,1) and DATE(2009,7,31) respectively.