To elucidate the value of conservative operation for aortic regurgitation, all consecutive patients operated on between July 1988 and July 1990 were reviewed. Of 251 patients with aortic regurgitation, 107 (42.6%) had nonprosthetic operation. The mean age was 23 years, and 90 patients (84.1%) were rheumatic. Two techniques were used: repair (annular and leaflet plasties, 69 cases) and cusp extension with glutaraldehyde-treated pericardium (25 bovine, 13 autologous). There were two hospital deaths (1.8%), both in the repair group, and no late deaths or embolic events. Only 5 patients (4.7%) were anticoagulated. In the repair group there were 12 reoperations, four (5.9%) due to aortic and eight to mitral dysfunction. In the cusp extension group there were two reoperations due to mitral dysfunction. Echocardiographic follow-up showed better results with cusp extension. In conclusion, conservative operation for aortic regurgitation is possible in a high percentage of young rheumatic patients and does not require anticoagulation. Cusp extension is more reliable than repair in terms of early results, although its long-term durability is not yet known.