The prevalence of obesity has reached epidemic proportions. Conceptualization of obesity as a chronic disease facilitates greater understanding its treatment. The NIH Consensus Conference on Gastrointestinal Surgery for Severe Obesity provides a framework by which to manage the severely obese--specifically providing medical versus surgical recommendations which are based on scientific and outcomes data. Medical treatments of obesity include primary prevention, dietary intervention, increased physical activity, behavior modification, and pharmacotherapy. Surgical treatment for obesity is based on the extensive neural-hormonal effects of weight loss surgery on metabolism, and as such is better termed Metabolic Surgery. Surgery is not limited to the procedure itself, it also necessitates thorough preoperative evaluation, risk assessment, and counseling. The most common metabolic surgical procedures include Roux-en-Y gastric bypass, adjustable gastric band, sleeve gastrectomy, and biliopancreatic diversion. Surgical outcomes for metabolic surgery are well studied and demonstrate superior long-term weight loss compared to medical management in cases of severe obesity.