The major factors contributing to the recommencement of clinical heart transplantation in the United Kingdom last year were the steadily improving results from Stanford University, the clarification of the diagnosis of brain death, and advances in preserving donor hearts. Twelve men aged 16 to 52 years received heart transplants at Papworth Hospital from January 1979 to July 1980. Six had cardiomyopathies and six ischaemic heart disease. The donors were aged 16 to 35 (mean 21) years. A combination of road and air transport was used to transport the heart to Papworth in seven cases. The total donor heart ischaemic time ranged from 108 to 171 minutes (mean 151), and early graft function was satisfactory in all cases. Postoperative management was directed towards preventing rejection and infection. Equine antihuman thymocyte globulin, prednisolone, and azathioprine were used for immunosuppression. Endomyocardial biopsy was performed every 10 to 14 days during the early postoperative period. There were three deaths: one at 17 days from brain damage and two at 59 and 76 days from rejection. Of the remaining nine patients six left hospital and three returned to work. The number of patients who might benefit from heart transplantation is large, but the cost is high. The cost would fall if an effective non-toxic immunosuppressive agent were developed. Meanwhile, a careful evaluation of the benefits of heart transplantation should continue. © 1980, British Medical Journal Publishing Group. All rights reserved.