In the years 1963--1977, the pathology department of the University of Colorado Medical School did 93 autopsies of patients with liver transplants. Fifteen of these patients had received a second graft. Sepsis was the greatest single cause of death or failure, and fungi and other organisms often considered opportunistic were frequent pathogens. Problems relating to removal of the liver from the donor, emplacement of the graft in the new host, and maintenance of the graft during the prolonged procedures together offer a monstrous challenge to the transplantation surgeon. All of these problems, classed as technical, include as complications infarction of the graft as the result of prolonged ischemia and blood loss or shock due to various causes, and all may produce alteration in structure of the liver; such changes may be misinterpreted as rejection. Rejection was a major cause of failure in only 5 patients, although the immunosuppression employed to control it contributed to the sepsis that so often was lethal. Hyperacute rejection was not observed in any of these transplanted livers, although 15 of these patients received a second transplant. Two of the patients whose grafts failed due to rejection had changes that indicated progression to an early stage of cirrhosis. We conclude that despite the persistent problems the liver is an organ peculiarly favorable for transplantation.