Abstract: An Internet or intranet based document retrieval system contains a database that relates document word-pair patterns to topics. In response to a word submitted by a requestor, the system retrieves documents containing that word, analyzes the documents to determine their word-pair patterns, matches the document patterns to database patterns that are related to topics, and thereby assigns topics to each document. If the retrieved documents are assigned to more than one topic, a list of the document topics is presented to the requestor, and the requestor designates the relevant topics. The requestor is then granted access only to documents assigned to relevant topics. A knowledge base linking search terms to documents and documents to topics is established and maintained to speed future searches.