Between February 1983 and July 1987, twelve patients underwent heart-lung transplantation at the University of Cape Town and the University of Munich. The patients included eight men and four women, whose ages ranged from 15 to 49 years (mean, 27 years). The underlying pathologic condition was idiopathic primary pulmonary hypertension in five cases, Eisenmenger's syndrome in four cases, idiopathic pulmonary fibrosis in one case, diffuse fibrosing alveolitis in one case, and chronic emphysema in one case. The immunosuppressive regimen consisted of cyclosporine A, azathioprine, and rabbit antithymocyte globulin (RATG) during the first 2 postoperative weeks; RATG was subsequently replaced by methylprednisolone. Pulmonary rejection frequently occurred in the absence of cardiac rejection; in one case, however, this situation was reversed. Two patients required retransplantation, which was undertaken for caseating pulmonary tuberculosis with obliterative bronchiolitis after 1 year in one case and for early pulmonary insufficiency after 2 days in the other case. There were no operative deaths, but three early deaths occurred, owing to respiratory insufficiency of unknown origin (10 days postoperatively), multiorgan failure (10 days postoperatively), and acute liver dystrophy (11 days postoperatively). Five weeks after operation, a fourth patient died of multi-organ failure. There were five late deaths, all of which resulted from infectious complications. Three patients, including one who underwent retransplantation, remain alive and well, 10 to 36 months postoperatively.