Abstract: An electronic bill presentment and payment system comprises a billing database for storing billing data representing amounts payable to a billing client from a paying client. An application server receives a plurality of instruction files, each representing a transaction for reading or manipulating billing data, performing the transaction utilizing data included in the instruction file, and providing a data response file complying with a predetermined format. A presentation server is coupled to the application server and includes a document database. The document database includes a plurality of document style sheets, each for presenting response data in a predetermined document format corresponding to one of the clients. The presentation server receives the response file and generates a client document utilizing data extracted from the response file and the document style sheet corresponding to the client.