Nonalcoholic fatty liver disease (NAFLD) remains a leading cause of chronic liver disease. In the context of NAFLD, the presence of nonalcoholic steatohepatitis (NASH) portends an adverse prognosis with greater risk of liver fibrosis and cirrhosis. Although liver biopsy is the keystone of patient management in NAFLD, it is also increasingly clear that such evaluation has its limitations. The availability of biochemical markers of NAFLD and NASH has tremendous potential to radically alter management strategies for these conditions, as well as to monitor disease activity. Our article provides an overview of biomarker discovery and selection in the setting of NAFLD and highlights future directions in the field. (C) 2009 The WJG Press and Baishideng. All rights reserved.