This review summarises the present knowledge on weight loss treatment. Weight loss leads to improvement or even remission of obesity-related co-morbidities. The greater the weight loss, the greater the effect. Significant weight loss may be obtained through dietary interventions alone or in combination with pharmacotherapy. Bariatric surgery continues to be the most effective intervention for obesity but is available only to those with the highest BMIs and the highest risk of complications. Access to weight loss treatments is currently limited.