Obesity in the United States has reached levels that could qualify as epidemic. Over 25% of US adults now may be defined as obese (body mass index [BMI] > 30 kg/m²). The health implications posed by this condition involve a wide spectrum of disease states, including diabetes, steatohepatitis/nonalcoholic fatty liver disease (NAFLD), cholelithiasis, and hypertension, as well as neuromuscular and cardiovascular complications. Efforts to address the issue of obesity should involve a multidisciplinary approach in which gastroenterologists play a key role. This implies a role in both the primary treatment and recognition of the associated problems, as well as in the management of postoperative complications.