The metabolic syndrome was designed to identify individuals at high risk for the development of type 2 diabetes and cardiovascular disease. Compared with whites, blacks have higher rates of diabetes and cardiovascular disease. Paradoxically, blacks have a lower prevalence of the metabolic syndrome. According to the criteria set by National Cholesterol Education Treatment Program-Adult Treatment Panel III, to diagnose the metabolic syndrome, 3 of 5 characteristics must be present. These characteristics are low high-density lipoprotein levels, increased triglyceride levels, central obesity, hypertension, and fasting hyperglycemia. Examining each of these factors individually, blacks are more likely than whites to have obesity, hypertension, and diabetes. In contrast, blacks are less likely than whites to have either elevated triglyceride or low high-density lipoprotein levels. Ethnic differences in lipid levels may largely explain why blacks have a lower than expected prevalence of the metabolic syndrome. In this review we will describe in children and adults ethnic differences in the epidemiologic study of conditions associated with the metabolic syndrome, as well as focus on each of the parameters of the metabolic syndrome. Overall, we conclude that an ethnic-specific formulation of the lipid criteria in the metabolic syndrome may lead to better identification of blacks at high risk for development of diabetes and cardiovascular disease.