=sumproduct(a1:a100,c1:C100)

You need to adjustt the ranges to match your spead sheet. The number of row
for column a and column c need to be the same

"Helen" wrote:

Hi,

I'm trying to do the following:

Count how many cells (rows) in coloumn A that has the value 1 in Column C
AND value 1 in Column D...

How do I go about this?

Thanks,

Helen