Diabetes is a major public health problem with serious complications. In 2002, the Centers for Disease Control estimated that 18.2 million people in the United States had diabetes. One in every 400 to 500 adolescents is diagnosed with type 1 diabetes mellitus (T1DM), and pediatric type 2 diabetes mellitus (T2DM) represents an emerging public health concern. The Children's Hospital of Philadelphia (CHOP) identified 337 children with T2DM through 2004. These children were mostly female and obese with a strong family history of T2DM. One patient's course of treatment for 1.5 years after initial presentation is described. Nineteen percent of the patients at CHOP were diagnosed with a neuropsychiatric illness before T2DM onset, further complicating their treatment. There is an imperative need for large-scale studies investigating the pathophysiology, treatment, and complications of T2DM in adolescents and youth.