Newly published data suggest that targeting fatty acid-binding protein 4 (FABP4), an intracellular protein involved in lipid transport in adipocytes and an active adipokine, is a promising approach for the treatment of type 2 diabetes mellitus and fatty liver disease. In leptin-deficient (ob/ob) and diet-induced obese (DIO) mouse models of obesity, a monoclonal antibody (mAb) targeting serum FABP4 (designated CA33) increased systemic insulin sensitivity, reduced fasting blood glucose levels, fat mass and liver steatosis, and improved systemic glucose metabolism. Using hyperinsulinaemic–euglycaemic clamp studies, the antidiabetic actions of CA33 were shown to be associated with peripheral glucose utilization and hepatic glucose production. The findings, published in Science Translational Medicine, support the further development FABP4-targeted therapies as a potential treatment for metabolic diseases.