The introduction of cyclosporine A in 1980 greatly improved the survival of children with end-stage liver disease undergoing orthotopic liver transplantation. The average 1-year survival rate following hepatic transplantation increased from 30% in 1963 to 70% in 1980. This report summarizes the initial experience of two pediatric hospitals in Montreal--Hôpital Ste-Justine and Montreal Children's Hospital. Since December 1985, 13 orthotopic liver transplantations have been performed in 11 patients: six females and five males. The median age was 18 months (range, 13 months to 17 years) and the median weight was 10 kg (range, 8.5 to 38 kg). The indications for transplantation were biliary atresia (5 patients), tyrosinemia (2 patients), biliary hypoplasia (1 patient), Amerindian cirrhosis (1 patient), Crigler-Najjar syndrome, type I (1 patient), and fulminant non-A, non-B hepatitis with grade IV encephalopathy (1 patient). Immunosuppression was ensured by cyclosporine A, azathioprine, and steroids. The function of 11 grafts was immediate following revascularization of the grafts. One graft had delayed function due to preservation injury, and one had primary nonfunction. Surgical complications included bile peritonitis (1), ruptured aneurysm of an aortic conduit (1), and thrombosis of the hepatic artery necessitating retransplantation (2). Three of our patients died, one from postoperative cerebral edema, one of primary nonfunction of the graft, and one of ruptured aneurysm of an aortic conduit. Our overall survival rate was 72% with a follow-up of 3 to 32 months. Pediatric liver transplantation can now provide successful treatment and cure of liver diseases considered, until recently, dismal and hopeless.