xl2007 added an =countifs() formula.

But in any version of excel:

=sumproduct(--(d1:d10="x"),--(a1:a10="b"))

Adjust the ranges to match--but you can't use whole columns (except in xl2007+).

=sumproduct() likes to work with numbers. The -- stuff changes trues and falses
to 1's and 0's.

Bob Phillips explains =sumproduct() in much more detail he
http://www.xldynamic.com/source/xld.SUMPRODUCT.html

And J.E. McGimpsey has some notes at:
http://mcgimpsey.com/excel/formulae/doubleneg.html

JCRICKET wrote:

I need to count the number of items that meet a certain criteria in two
different cell arrays. I am having serious trouble figuring this out. I
would like to count as 1 only if cell D="x" and Cell A="B". I have tried a
couple of different ways to do this but keep getting errors.

--

Dave Peterson