Social networking sites (SNSes) like MySpace.com and Facebook attract large numbers of mostly young users who are eager to engage with their favorite brands. But most marketers use traditional marketing tactics like run-of-site advertising and static microsites to push messages into these networks. Instead, to realize the full value of marketing on SNSes, marketers should be prepared to engage in a personal relationship with users by providing something of value. Promotions are good in this context, but even better are information or brand elements that users can pass on to their friends.