Summary: Nonalcoholic fatty liver disease (NAFLD) occurs in 20-¬25% of the population in highly developed countries. In 10-¬15% of patients the disease takes the form of steatohepatitis (NASH), a risk factor for increased morbidity and mortality related to liver failure, hepatocellular carcinoma, and also cardiovascular complications and extrahepatic neoplasms. The epidemic of NAFLD has created real and unmet diagnostic and therapeutic needs. The main diagnostic shortcomings are low awareness of NAFLD in the medical community and society, poor recognition of metabolic risk factors for NAFLD and lack of noninvasive tools to diagnose NASH. In treatment we still await new drugs able to reduce hepatic necroinflammation and fibrosis.