According to an embodiment of the present invention, techniques are disclosed for providing promotions to users of communication networks, such as the Internet. Information related to a plurality of promotions, including promotions information and rules associated with the promotions, are stored at a promotions management system. The promotions management system receives a query from a vendor system requesting promotions to be shown to a user browsing a particular item at the web site of the vendor. The promotions management system responds to the query by determining a set of promotions to be presented to the user based on the information contained in the query, the information related to the promotions, and other information accessible to the promotions management system. The promotions in the set of promotions are then presented to the user.