The implantation of large numbers of cardiac pacemakers and the increasing sophistication in engineering techniques has resulted in the demand for computer-assisted pacemaker management systems to remain on top of the available programmable features of the pacers as well as being able to access the follow-up data of pacemaker patients. A pacemaker patient management systems is introduced (PA-TIENTLOG) that has been used in the clinical environment for a number of years. The menu-guided program is easy to handle and features a patient card for administration data, an implantation card for the technical data of the pacer, and a follow-up card where a large number of follow-ups can be stored side by side which are easily graphically displayable. An extensive statistical program, letter functions, automatic back-up and on-line communication with external equipment through an RS 232C interphase and a parallel adapter are available. The data base in Frankfurt holds 8,000 patients, 10,000 interventions and more than 30,000 follow-ups, the existing data base needs 20 M bytes storage space. Up to 96 different pacer types with their specific features can be introduced into the system. Software and hardware design complies with the recommendation of the NASPE Computer Committee.