The invention provides a classification engine for classifying documents that makes use of functions included in a similarity search engine. The classification engine executes a classify command from a client that makes use of similarity search results, and rules files, classes files, and a classification profile embedded in the classification command. When the classification receives a classify command from a client, it retrieves a classification profile and input documents to be classified, sends extracted values from the input documents based on anchor values to a XML transformation engine to obtain a search schema, requests a similarity search by a search manager to determine the similarity between input documents and anchor values, and classifies the input documents according to the rules files, classes files, and the classification profile. The client is then notified that the classify command has been completed and the classification results are stored in a database.