A system and method for comparing search queries provided by a user with content items available in an index. Search queries are received and stored in a database query log. Content items are located on a network and stored in an index. A value is generated for concepts and categories in the query log and the index. The value for different categories and concepts in the query log is compared with the value for different categories and concepts in the index. A need for content is determined for a given concept and category, which may be communicated to content providers, e.g., web site operators.