A CSS partner is a Comparison Shopping Services Partner, which means it is a company or website that is in the business of comparing products and prices. Buy collecting the prices and specifications from different retailers it is possible to give any consumer the best information and the right price. A CSS partner (like Bigshopper for example) is a company that works with several reatailers and Google for example to get the most out of it. Being a CSS Partner with Google gives some advantages in Adwords campaigns The real winner is of course the consumer, when getting on a CSS site you get the best deal available without any hassle