The global obesity epidemic is an ever-growing concern, with approximately a third of North Americans fitting the criteria for obesity. It is therefore important to assess obesity and be able to classify its severity. The Body Mass Index (BMI) classification is the most widely used tool for assessing obesity. However, due to inaccuracies in BMI in measuring body composition in the obese population, other tools like anthropometry, bioelectrical Impedance Analysis (BIA) and Quantitative Magnetic Resonance (QMR), are being evaluated. The regulation of obesity requires a multidisciplinary approach, which combines diet, lifestyle, and pharmaceutical regimens. However in the morbidly obese population, bariatric surgery is the only proven treatment modality, with an average excess weight-loss of over 60%. The specific types of bariatric surgeries place different emphasis on restriction of oral intake of nutrients versus reducing the absorption of those nutrients in the gastrointestinal tract. While these procedures do achieve clinically significant weight-loss and comorbid resolution, their lack of availability, cost and potential morbid complications have led to other procedures, specifically endoluminal techniques, emerging as possible candidates for the regulation of the obesity epidemic. In this article, we review the assessment of body composition in the obese population, the regulation of this obesity with bariatric surgery and emerging techniques in the field of bariatrics.