What if I wanted to have the criteria text in column C and wanted to sum the
values in Column B that matches the citeria specified in Column C in Column
A?
A B C
Salary 500 Salary
Bonus 400 Bonus
Fringe 300 Fringe
Travel 100
Entertainment 100

Someone suggested using the following, if I were specifying the criteria in
quotes. And this works.
=SUMPRODUCT(--(A1:A5={"Salary","Bonus","Fringe"})*(B1:B5))

But I want to reference Column C for the criteria. I tried doing
=SUMPRODUCT(--(A1:A5={C1,C2,C3})*(B1:B5))
but Excel returns an error message if I try this formula. Any help would be
much appreciated.

Thank you!