Methods, systems, and apparatus include computer programs encoded on a computer-readable storage medium, including a method for providing content. An indication is received from a content sponsor of a first collection of entities, sharing common characteristics, to be used for selection criteria for presenting a first content item. References to the first content item and selection criteria are stored. A query is received including terms or phrases associated with a first entity. It is determined that the first entity is included in the first collection of entities, wherein the terms or phrases do not include the first collection. Eligible content items are identified, each being associated with selection criteria including criteria specifying the first collection of entities. At least a portion of the first collection of entities is provided for presentation along with search results, including providing one or more of the eligible content items and the first content item.