During the years 1977 to 1983, 1,458 pacemakers were implanted or reimplanted in our clinic. Seventy-nine patients were treated during the same period for pacemaker system infections. The time interval between the preceding surgical maneuver and the manifest infection was 11.9 +/- 10.2 months in the catheter fistulas and 12.2 +/- 11.5 months in the pacemaker pocket infections. Forty-one of 79 infections (52%) occurred following the first generator implantation. In 33/43 (76.7%) patients with partial pacemaker system removal, recurrent infection occurred 19.6 +/- 17.2 months later. The infection was treated with similar surgical maneuvers resulting in subsequent infections in 9 patients after 9.8 +/- 7.2 months. In the patients with total pacemaker system removal infection developed in 2/25 (8%). The infection resulted in septicemia in 9 patients. Major surgical intervention was necessary for removal of the infected endocardial electrode in 7 patients. According to our experience there are no grounds for partial removal of the pacemaker system if infection occurs. The primary results may be satisfactory but re-infection will appear in the majority of the patients after a period of several months.