A frame represents a concept with a set of roles and a set of linguistic rules. If a linguistic rule is satisfied, by a unit of natural language discourse (UNLD), the frame is invoked and a frame instance produced. A frame instance specifies how the UNLD, with particular values drawn from the UNLD, fulfills the roles of the frame. A frame-based search, of target content, is accomplished in response to a frame-based user query. The search result is comprised of records, where each record is a result of a match, of the frame-based query, at a location in the target content. If the frame-based query is implicit, a match requires only that the location of the target content invokes the appropriate frame. If the frame-based query is role-specific, in addition to invoking the appropriate frame, a query search term needs to be found in the value for a role of the frame instance produced.