Evidence is‘absolutely critical’to the successful implementation of any disease management (DM) programme, according to Dr Scott Weingarten, Director of Health Services Research at Cedars-Sinai Health System in California, US. To change the behaviour of physicians and other healthcare professionals, you need to be able to provide good scientific evidence that the desired change in practice will result in improved patient outcomes. Delegates atThe Disease Management Congress[San Francisco, US; January 1997] heard Dr Weingarten outline some of the determinants of a successful DM programme, and discuss examples of successful DM programmes in the areas of congestive heart failure, diabetes mellitus and uncontrolled hypertension.