REFERENCE UPDATE (a trademark of Research Information Systems, Inc.) is a diskette-based service which provides subscribers with a weekly update on the latest publications in biology and medicine. REFERENCE MANAGER (a registered trademark of Research Information Systems, Inc.) is a microcomputer-based software package developed to manage selected references for quick retrieval and bibliography generation. These two systems allow scientists to build and update a personalized data base of references. The following article gives an overview of REFERENCE UPDATE and REFERENCE MANAGER and provides a description of the various functions each system offers.