There are many companies that specialize in affiliate marketing. They are most commonly known as Affiliate Marketing Managers or Affiliate Marketing Service Providers.

Affiliate marketing is the process of using one website to drive traffic to another and is a form of online marketing.

There are two parties involved, one is the provider of the services or products, and the other is the promoter for these products and services. This is where the Affiliate Programs come into play in that they join forces to network both the provider and the promoter and assist in the necessary aspects of that relationship.

Some well known affiliate marketing groups include:

LinkShare
Shareasale.com
Commission Junction
ClickBank
Pepperjam

These are just to name a few.