Although prevention is clearly a logical first step in the management of the obese Type 2 diabetic patient, such programmes have had little long-term success. Diet, exercise and behavioural modification still form the cornerstones of treatment and relatively small weight loss results in improvement of all major obesity-related co-morbidities, including Type 2 diabetes. The obese diabetic patient faces extra impediments to weight loss, including the adverse effects of diabetic medication, poor glycaemic control and diabetes-related complications. New drugs may offer some additional help, in general by providing the benefit associated with the weight loss as such. Bariatric surgery can produce major long-term weight loss in the severely obese.