Thirty patients, 18 males and 12 females, with PSC have been studied between 1972 and 1986. In nine PSC was associated with ulcerative colitis (30%), in 4 with Crohn's disease (13%) and 17 were free of any chronic bowel disease. Four of these 17 were siblings. Alkaline Phosphatase, Gamma GT, total bile acids and 7-alpha-hydroxilated bile acids were elevated in all patients. In 14 patients plasma and urinary copper as well as ceruloplasmin were studied, showing the copper in all cases and ceruloplasmin in 10 cases elevated, 4 were normal. By means of cholangiography alterations of the extrahepatic ducts, the intrahepatic ducts, and both the intra- and extrahepatic ducts were seen in 13%, 27% and 40% of the cases, respectively. Alterations of the pancreatic duct were observed by pancreatography in 21% of cases. 40% of the PSC-patients had also a Sjögren's syndrome, while 3% were associated with diabetes mellitus Type I and II, psoriasis and red lichen planus, iridocyclitis and hepatic hemangioma.