In Tayside region, from 1976 to 1986, the number of permanent pacemakers implanted per year more than doubled, with the increase particularly marked over the latter five years. In order to determine the factor(s) which had caused this increase in implantation rates, a retrospective analysis of patients undergoing pacemaker implantation during the period 1981-1986 was undertaken. No change in the number of elderly in the population, age of patients, mode of referral, waiting time before insertion or clinical indications for pacing was observed to account for this change. The advent of ambulatory ECG monitoring may have contributed to this increase, but the appointment of an extra cardiologist in Tayside in 1982 was believed to have been more important. These results suggest that the number of pacemakers implanted in a region is highly dependent on the number of cardiological staff in that region available for their insertion.