Criteria for selection of appropriate candidates for bar­iatric surgery have been established to minimize surgical complications and to maximize the benefit of these important and limited procedures. The preoperative workup should evaluate a patient’s medical, nutritional, mental and functional health status. Special attention should be given to the care of patients living with type 2 diabetes (T2DM) who are considering bariatric surgery to minimize complications from uncon­trolled diabetes in the perioperative period. Because of the risks of postoperative complications associated with tobacco use, cessation prior to bariatric surgery is mandatory and should be maintained lifelong. In patients living with severe obesity, bariatric surgery, in combination with behavioral interventions, is a more effective option for long-term weight loss and control of chronic conditions, such as T2DM, hypertension, sleep apnea and dyslipidemia, as well as other conditions associated with increased adiposity.