The University of Toronto liver transplant program began in 1985 at a time when the procedure had already evolved from an experimental form of surgery to an accepted treatment for many forms of liver failure. The program was established not only to provide clinical care for patients but also to address academically the barriers which impeded success. The program brought together experts in medicine, surgery, pathology, and the basic sciences of immunology, virology and molecular biology. Our group has had a special interest in transplantation for viral hepatitis. We demonstrated the role of HBV DNA as a prospective factor in both viral recurrence and survival. We further studied a number of agents to prevent re-infection including PGE, HBIG and more recently lamivudine. Although the short-term results of transplantation for HCV appear excellent, reinfection of the graft and development of chronic hepatitis and cirrhosis may make long-term results problematic. Therefore, we have directed attention to studies of pathogenesis and treatment of HCV in liver transplantation. Our studies have demonstrated a unique role for ribavirin as an immunomodulatory agent which can benefit the course of posttransplant HCV. Future studies will examine combination therapy in an attempt to eradicate the virus. Our group also has been interested in PNF and FHF and have demonstrated a positive effect of PGE in this setting. As we look to the future, the greatest challenges facing transplantation are the shortage of organ donors and the toxic effects of long-term immunosuppression. Our group now has established research efforts both in tolerance induction and xenotransplantation which we feel are necessary to make transplantation an effective, universal treatment for end stage organ failure.