Non-alcoholic fatty liver disease (NAFLD) is strongly associated with insulin resistance, and its prevalence is rising in parallel with worldwide increases in obesity and type 2 diabetes. However, the nature of this relationship remains debatable. In particular, it is unclear whether insulin resistance causes NAFLD or hepatic steatosis per se reduces insulin sensitivity. This review will examine data from recent studies on the link between insulin resistance and NAFLD, focusing on studies that have attempted to dissociate fatty liver and hepatic insulin resistance.