The results of search queries are augmented with behaviorally related items. Items that are behaviorally related to a particular search query may be identified by analyzing the item selection actions of users who submit the particular search query. For example, if a relatively large number of users who submit a particular search query eventually select a particular item (e.g., during subsequent searching or browsing), that item may subsequently be included in the search results for the search query, even though the item may not match the search query.