Aortic valve replacement in the young patient represents a serious problem in terms of anticoagulation and limited durability of the bioprosthesis. In order to determine the possible advantages of conservative surgery, consecutive patients with aortic regurgitation, aged below 35 and operated upon between July 1988 and July 1990 were analyzed. There were 149 patients (mean age 22 years). The aetiology was rheumatic disease in 122 (81.9%) and 83.2% of the patients were in NYHA class III-IV. Sixty-one valves were replaced (AVR) and 88 (59%) were repaired by a variety of techniques (annuloplasty, cusp unrolling, resuspension or extension). The mean ischaemic times for isolated aortic regurgitation were 73.6 mins for AVR and 80.5 mins for repair. Associated mitral surgery was performed in 94 patients (63%); 33% of these had a valve replacement and 67% a repair. In the AVR group there was 1 hospital death (2.2%), 2 late deaths (3.3%), 3 major embolic events (5%) and one reoperation for infection. In the repair group there were 2 hospital deaths (2.4%), but no late deaths or embolic events. Twelve patients required reoperation which was performed without mortality; this was due to aortic dysfunction in 4 cases (4.6%) and mitral dysfunction in 8. It is concluded that aortic valve conservation in a young, predominantly rheumatic, population can be performed in a significant number of patients with a low mortality and morbidity.