Every obese person presents a different management problem, although the following general principles can be applied: (1) It may be easier to prevent obesity than to treat it. (2) Lifelong modification of eating habit is the corner stone of effective therapy. (3) Group therapy combined with a behavioural modification programme provides a method of assisting many subjects. (4) Drug therapy is best justified if there is a short-term need to produce weight loss. (5) Radical therapy should be restricted to the morbidly obese and is best supervised by units with special expertise.