Type 2 diabetes mellitus (DM) has historically been considered an adult disease. However, the incidence of type 2 DM has increased dramatically in pediatric populations in recent years. This increase parallels the recent rise in childhood obesity and has been greatest among minority adolescents. Differences between African-American and white American youths are discussed, including risk factor differences that may help to account for the overwhelming number of African-American children with type 2 DM as compared with white children. African-American youths have higher rates of insulinemia, obesity, family history, and acanthosis nigricans than their white counterparts. In addition, despite similar declines in insulin action during puberty, there is no compensatory increase in insulin secretion in African-American children, contrary to the observation in white children. These differences are likely to have a genetic basis modulated by environmental and lifestyle influences. Treatment of type 2 DM should focus on identifying individuals at risk and instituting lifestyle changes to reduce the risk and stem the development of DM.