Endoscopic retrograde cholangiograms from 23 patients with primary biliary cirrhosis (PBC), 10 controls with either normal livers or hepatocellular disease, and 4 patients with sclerosing cholangitis, were compared. Of the PBC group, 39% had gallstones. The calibers of the common bile duct and left and right intrahepatic ducts were comparable in the PBC and control groups. The small intrahepatic ducts, while normal in the control group were abnormal in 7 of the 23 PBC patients. These small ducts were irregular in caliber and had a tortuous course. The changes were not related to the presence of gallstones or the duration of the disease, but all the patients had histologically proven cirrhosis. Two patients with cirrhosis had normal intrahepatic ducts. We conclude that whereas the major bile ducts are normal in PBC, there is a high incidence of gallstones (39%), and the changes that do occur in the intrahepatic ducts are probably related to the distorted hepatic architecture due to cirrhosis and may be used as a sign that cirrhosis has supervened.