Methods, systems, and apparatus, including computer programs encoded on computer storage media, for identifying query refinements from sibling queries. In one aspect, a method includes associating each of a plurality of parent queries with a respective group of one or more child queries for the parent query, identifying one or more candidate sibling queries for a particular child query, selecting one or more final sibling queries for the particular child query from the one or more candidate sibling queries, and associating the final sibling queries with the particular child query as query refinements.