Between 1975 and 1983, 136 patients aged over 70 underwent open heart surgery: aorto-coronary by-pass in 67 cases, valve replacement in 46 cases, combined valve and coronary surgery in 20 cases, resection of a left ventricular aneurysm in 2 cases and closure of a ruptured septum in 1 case. There were 13 deaths in the short-term (9.6%). Operative mortality for aorto-coronary by-pass was 4.5%, and that of valve replacement 4.4%, whereas for the combined procedures it was 35%. Non-fatal post-operative complications were frequent, occurring in 40% of patients. Life-table analysis showed 77% survival at 5 years. Of the 111 patients who left hospital, only one was lost to follow-up. At an average follow-up of 26 months, there were 84 patients in functional class I, 17 in class II and 9 in class III. Complications related to the presence of a prosthetic valve occurred in only 3 patients, none of whom required reoperation during the follow-up period. In the elderly, open heart surgery can therefore be carried out at relatively low risk, except where combined procedures are concerned. The long term history, together with the degree of functional improvement achieved, justify cardiac surgery even in the elderly.