Individuals with psychiatric disorders tend to have excessive morbidity. They typically have high rates of respiratory illnesses, infectious diseases, substance abuse (including smoking), obesity, diabetes mellitus, and cardiovascular disease (CVD). Persons with schizophrenia and affective disorders also have a high prevalence of risk factors for CVD, such as diabetes and obesity, which are on the order of 1.5 to 2.0 times higher than in the general population; this translates into increased mortality rates due to CVD. The use of certain psychotropics results in metabolic sequelae, such as obesity, dyslipidemia, glucose dysregulation, and the metabolic syndrome. These sequelae exacerbate the already elevated risk of CVD and diabetes in this group of people. Therefore, the use of psychotropic agents that result in, for example, excessive weight gain not only add another complication for physicians managing a patient with schizophrenia but also may have serious prognostic and cost implications with respect to treatment-related diabetes and coronary disease incidence. The recent American Diabetes Association (ADA) Consensus Panel concluded that some agents are associated with greater diabetes risk than others. The current review describes the prevalence of the metabolic syndrome in people with affective disorders and schizophrenic populations, its prognostic relevance, and its exacerbation among patients treated with particular psychotropic agents, including certain atypical antipsychotics, selective serotonin reuptake inhibitors, and mood stabilizers. The costs associated with the treatment of the metabolic syndrome, diabetes, and coronary heart disease in populations with schizophrenia are also described.