Experience with renal transplantation indicates failure of the graft is usually due to immunological rejection. In a previous study of human liver transplantation, rejection was the major cause of transplant failure in 4 of 17 patients (24%); in this review of 76 liver transplantations, 64 of which survived the 1st postoperative wk, rejection was the primary cause of graft failure in only 4 of these 64 cases (6%). The 2 most common causes of transplant failure were technical difficulties with the operative procedure and sepsis; these accounted for 47 (62%) graft failures of the total of 76 transplants. Biliary obstruction and sepsis are more common causes of liver failure than rejection, and patients wtih recurrent jaundice are now studied intensively for evidence of obstruction. Only after obstruction is excluded is immunosuppression intensified. These results are a basis for optimism concerning the future of liver transplantation in management of potentially fatal liver disease.