Primary sclerosing cholangitis (PSC) is a chronic cholestatic liver disorder characterized by strictures and dilatations of the biliary tree. The median survival has been reported to be 12 years from diagnosis but patients diagnosed during the last decade have been shown to have longer survival of a median of 18 years. Small duct PSC seems to be an entity of its own and rarely progresses to large duct PSC and the prognosis of small duct PSC is much better than in large duct disease. Cholangiocarcinoma does not develop in patients with small duct PSC according to recently published studies. Autoantibodies binding to biliary epithelial cells have been demonstrated in sera from patients with PSC but the pathogenic role of these remains to be determined. It is suggested that inflammatory bowel disease is accelerated after orthotopic liver transplantation. MR cholangiopancreatography is increasingly used in clinical practice and has been reported to have similar diagnostic accuracy as ERCP. However, lack of standardization of this novel technology makes it unclear if it can supersede ERCP as a diagnostic tool in PSC at the present time. Better diagnostic tests to detect cholangiocarcinoma in patients with PSC are urgently needed.