Between January 1983 and December 1987, 103 patients who had hilar biliary obstruction (59 men, 44 women, median age 73 years) were referred to our institution. The causes of hilar biliary obstruction were carcinoma of the bile ducts (55), hepatic metastases or hepatocellular carcinoma (30), and carcinoma of the gallbladder (18). When endoscopic retrograde cholangiography was performed, the stricture was classified as type I in 28%, type II in 41%, and type III in 31% of the patients. In 92 patients, we tried to insert endoscopically a 10, 11, or 12 F Amsterdam type prosthesis; it proved possible in 66 (74%), and the prosthesis proved functional without further procedure in 49 cases (53%); no combined percutaneous and endoscopic method was used. At death or discharge, 45 patients (49%) had a successful drainage. Cholangitis was the main procedure-related complication and occurred in 25 patients. The 30-day mortality was 43%. Results varied according to type of stenosis: successful drainage was performed in 15% of the patients with type III stenosis, compared with 86% when the stenosis was of type I. Under a multivariate analysis the independent prognostic factors of 30-day mortality were: (1) development of infectious complications after endoscopic attempt at drainage (P less than 0.0001), and (2) absence of successful drainage (P less than 0.0001). In conclusion, endoscopic endoprosthesis placement allows a sufficient drainage in 53% of the cases. In type III stenosis, the high rate of 30-day mortality leads us the conclusion that endoscopic drainage must be avoided.