Totalling up values that meet two criteria

Ive attached the relevant spreadsheet for reference.

I have 17 different "sites" and 3 different "goods" and i want to total up the "total cages" that meet the "site" and "goods" criteria for each different possibility. i.e site1 & goods1, site1 & goods2, site1 and goods3, site2 and goods1, site2 and goods 2 etc etc

I know i can use a DSUM to total up using 1 criteria but is there a formula for using 2 criteria?

Hope i make myself clear.

Thanks