Chronic aethylism has always been a major social as well as health problem. It may lead, at least in some patients, to steatohepatitis (ASH) which is known to progress to cirrhosis more rapidly. Because of the fact that the prevalence of obesity in association with the metabolic syndrome (insulin resistance) is strikingly increasing in the Western world, we will more and more often be faced with a second form of steatohepatitis, the so called non-alcoholic steatohepatitis (NASH). Clinical differentiation between these two entities may often be difficult. The use of the CAGE-questions as well as interviewing family members can help to indentify hidden alcohol abuse. Clinically, the presence of both diseases can only be speculated. To get the diagnosis, liver biopsy must be performed to show the typical histologic feature of fatty liver with hepatocyte necrosis as well as infiltration of polymorphcellular leukocytes. Histology cannot differentiate between ASH and NASH. Therefore, similar pathogenetic mechanisms are supposed. However, therapeutic approaches are different. Treatment of choice in ASH is alcohol abstinence, that of NASH the reduction of insulin resistance, primarily by weight loss.