 Abnormalities in peripheral glucose regulation and type 2 diabetes can occur more commonly in individuals with schizophrenia than in healthy subjects or in other psychiatric conditions. Antipsychotic treatment may contribute significantly to abnormalities in glucose regulation. Hyperglycemia can contribute to long-term cardiovascular disease risk that may already be increased in patients with schizophrenia due to higher rates of smoking, sedentary life style, obesity and under-treated hypertension and dyslipidemia. This project will characterize the effects on glucose control of the two most commonly prescribed newer antipsychotic medications, risperidone and olanzapine, in patients with schizophrenia. 