A modern approach to obesity acknowledges the multifactorial determinants of weight gain and the health benefits to be derived from weight loss. Foundational to any weight loss effort is lifestyle change, diet, and increased physical activity. The approach should be a high quality diet to which patients will adhere accompanied by an exercise prescription describing frequency, intensity, type, and time with a minimum of 150 min moderate weekly activity. For patients who struggle with weight loss and who would receive health benefit from weight loss, management of medications that are contributing to weight gain and use of approved medications for chronic weight management along with lifestyle changes are appropriate. Medications approved in the USA or European Union are orlistat, naltrexone/bupropion, and liraglutide; in the USA, lorcaserin and phentermine/topiramate are also available. Surgical management (gastric banding, sleeve gastrectomy, and Roux-en Y gastric bypass) can produce remarkable health improvement and reduce mortality for patients with severe obesity.