1. A method performed by an image search system of one or more computers, the method comprising: receiving a query from a client device; providing one or more image search results to the client device, each of the one or more image search results identifying a corresponding image resource and each of the one or more image search results including an image representation of the corresponding image resource; and providing one or more related queries to the client device, the one or more related queries having been determined to be related to the query, wherein each of the one or more related queries includes a preview image to be displayed at the client device, the preview image representing an image search result responsive to the related query.