Document management systems allow organizations to have greater control over the lifecycle of documents from creation through review, storage, retrieval and dissemination all the way to their destruction. Document management provides greater efficiencies in the ability to classify and reuse information. This document deals with issues of storage and retrieval processes of text documents in document management systems. Main focus is made on choosing an effective document format, means and methods for storing and retrieving documents. The paper suggests using XML as the base document format and relational database management system as backend storage of the document management system. A new modification of the standard Edge method for storing and retrieving XML documents from relational database management systems is introduced and the results of its performance experiment are presented. The experiment proves the performance superiority of the modified Edge method over its standard analogue.