A system and method for guiding a user in building a query are disclosed. The method includes providing an interaction space in which a user formulates a query using a plurality of query building blocks selected from a predefined set of query building blocks. The user's formulation of the query is guided. Guiding selection of at least a next building block is provided by at least one of a content-based mechanism which limits the selection of the next building block to those which will yield at least one result from an indexed collection of documents, a structure-based selection mechanism which limits the selection of the next building block to those which meet a predefined grammar, and a usage-based selection mechanism which proposes a next building block based on patterns of building blocks used in building prior queries. Each of these guidance mechanisms may be provided with the result that the next block proposed is informed by each of the mechanisms.