In e-commerce, sellers leverage relationships with each other and with one another's customers by setting up links between their sites.
Affinity marketing represents a major break from traditional mass marketing, observers agree.
Instead of acting on their own to broadcast the same message to millions of customers, organizations team together to attract customers with particular interests. Within the world of e-commerce, the concept generally translates into sharing referrals by using banner ads, icons and text links in an attempt to point customers to other sites that also meet users' individual proclivities, typically through personalization. David Schmitlein, marketing professor at University of Pennsylvania Wharton School, points out that affinity marketing originated in the credit-card industry. There, it describes programs designed to cash in on customers' feelings of affinity with groups like universities, nature conservancies and other types of charities. If the customer accepts a credit card emblazoned with the name of the affinity group, the organization benefits by getting a small percentage of the sales charged on the card.