Sibutramine is the first of a new generation of weight management drugs, and offers long-term control of weight when used as an adjunct to diet and exercise. This paper considers the criteria set down by the European Union's regulatory agency for its use and how this relates to the information now available on its efficacy, side-effect profile and benefits in different patient groups. The data presented relate to 18-65y olds; its use in other age groups has not been established. The EU licence permits continuous treatment for periods of up to 1y; the STORM study has now led the US Food and Drug Administration to extend clearance to 2y. The addition of sibutramine to a regimen of diet, exercise and lifestyle modification results in 3-5 times more patients responding to a weight-reduction programme, ie achieving more than 5% weight maintenance. Sibutramine is indicated for use in obese patients (BMI > 30 kg/m²) and also overweight patients with a BMI > 27 kg/m² who have additional obesity-related risk factors such as type 2 diabetes or dyslipidaemia.