A National Institutes of Health workshop on pharmacologic treatment of obesity concluded that pharmacologic agents may be effective in reducing body weight over an extended period of time. Drugs should be used as only one component of a comprehensive weight-reduction program, and additional research is needed on the long-term efficacy and safety of drugs for obesity, and especially for combinations of drugs. Improvement in comorbidities and risk factors of obesity should be used along with weight reduction as an outcome measure in clinical trials. Industry, professional societies, and governmental agencies should work together to explore the potential for drugs for obesity and to reassess the regulatory and administrative controls on the use of currently available drugs for obesity and on the approval process for future drugs.