This book is the proceedings of Falk Symposium 157, entitled ‘Chronic Hepatitis: Metabolic, Cholestatic, Viral and Autoimmune’, held in Freiburg, Germany, on 10--11 October 2006 (one of three symposia during the XIII Falk Liver Week 2006). It provides up-to-date information on new developments in the field of chronic hepatitis and its various entities. In recent decades we have learned how heterogeneous the clinical entity of chronic hepatitis has become. The liver, as the central organ of metabolism and detoxification, is more than ever a target of disease processes evolving from the spread of obesity in the western world. Apart from nonalcoholic steatohepatitis (NASH), alcoholic liver disease is still the most prevalent liver disease in the west. Alcohol-induced liver disease exhibits a broad clinical spectrum from alcoholic steatohepatitis to cirrhosis. Alcoholic hepatitis is a disease entity with a particular poor prognosis. Any liver disease of unknown cause is suspected as being drug-associated. Every new drug metabolized in the liver has the potential to damage the liver. Primary biliary cirrhosis has seen significant progress due to the identification of new risk factors based on new epidemiological studies. Interface hepatitis has become a prognostic marker as well as a therapeutic target. The treatment of autoimmune hepatitis has progressed significantly due to an individualized approach to immunosuppression.