A computer process is disclosed for selecting items to present or recommend to users based on the referring sites accessed by such users. The process includes tracking referrals of users from referring sites to a target site, and recording the item selections of the referred users from an electronic catalog of the target site. The process may also include analyzing the recorded item selections of the users to identify, for a particular subset of the referring sites, a set of items that correspond to group preferences of users referred to the target site by the subset of referring sites. These identified items may thereafter be presented to users who access a site that is a member of the subset of referring sites.