The treatment of obesity has met with limited success and clinically significant weight losses have been difficult to achieve and maintain. Screening to determine which patient will benefit most from treatment, emphasis on maintenance of weight loss and understanding individual weight trends and goals, all have demonstrated significant impact on long-term treatment outcome. Stunkard established a new classification of obesity according to severity and predicted outcome to treatment, distinguishing mild and moderate overweight from severe forms of obesity. Those who were classified as mildly obese were those who were most likely to be successful in traditional forms of treatment. A comprehensive study of this mildly obese population and normal weight maintenance behaviors provided important information on which to build future treatment interventions and/or effective strategies. This would be of particular importance in the prevention of obesity and progressive escalation of the obese state.