Treatment of patients with nonalcoholic fatty liver has typically been focused on the management of associated conditions such as obesity, diabetes mellitus, and hyperlipidemia as well as discontinuation of potentially hepatotoxic drugs. Nonalcoholic fatty liver associated with obesity may resolve with weight reduction, although the benefits of weight loss have been inconsistent. Appropriate metabolic control for patients with diabetes mellitus or hyperlipidemia is always recommended but not always effective in reversing nonalcoholic fatty liver. Promising results of pilot studies evaluating ursodeoxycholic acid, gemfibrozil, betaine, N-acetylcysteine, and alpha-tocopherol suggest that these medications may be of potential benefit in the treatment of patients with nonalcoholic fatty liver. These medications, however, need first to be tested in well-controlled trials with clinically relevant end points and extended follow-up. A better understanding of the pathogenesis and natural history of this condition will help to identify the subset of patients with nonalcoholic fatty liver at risk of progressing to advanced liver disease and, hence, the subgroup of patients who should derive the most benefit from medical therapy. In this article, we review (1) the existing medical therapy for patients with nonalcoholic fatty liver, (2) the emerging data from clinical trials evaluating potentially useful medications, and (3) the potential therapeutic implications of recent studies on the pathogenesis of this liver disease.