Nonalcoholic fatty liver disease is an increasingly recognized health problem. Its presentation ranges from simple steatosis to its inflammatory representation of nonalcoholic steatohepatitis. This Review considers various modalities that have been tried for nonalcoholic fatty liver disease, such as weight loss and/or exercise, thiazolidinediones, metformin, lipid-lowering agents and antioxidants, as well as considering treatments that are on the horizon.