The increasing prevalence of obesity and its related comorbidities represents an increasing burden for the Dutch health care and requires effective therapy. The primary treatment of obesity consists of lifestyle interventions directed at lifestyle change; in morbidly obese subjects only bariatric surgery is cost-effective in the long term, with respect to both weight loss and reduction in comorbidity. There is a new Dutch multidisciplinary practice guideline on the treatment of morbid obesity, in which the following aspects are covered: indications for surgery, pre-operative policy advice, considerations for the type of operation, and the short and long term follow-up after bariatric surgery. Patients between 18 and 65 years old are eligible for bariatric surgery if they have a BMI ≥ 40 kg/m2 or a BMI ≥ 35 kg/m2 in the presence of comorbidity. In adolescents under 18 bariatric surgery should only be performed in a research setting; in patients older than 65 years bariatric surgery can be performed exceptionally, preferably in a centre with large experience.