Over the past 20 years or so, the accuracy of using the conventional Riva-Rocci sphygmomanometer and Korotkoff's sounds to measure blood pressure has been questioned, and efforts have been made to improve measurements with automated devices.1 2 In the same period, the phenomenon of white coat hypertension has been recognised—whereby some patients who apparently have raised blood pressure actually have normal blood pressure when the measurement is repeated away from the medical environment; this has focused attention on methods of measurement that provide profiles of blood pressure rather than rely on isolated measurements made under circumstances that may influence blood pressure.3 These methods have included repeated measurements of blood pressure using the traditional technique, self measurement of blood pressure in the home or workplace, and ambulatory blood pressure measurement using automated devices.2 Ambulatory monitoring is advantageous because it gives multiple measurements throughout the day and night

This paper considers only the ambulatory measurement of blood pressure in adults. Its purpose is not to make a case for or against ambulatory measurement; others have already done so.4 5 Although the results of a number of ongoing, longitudinal studies are forthcoming, there is now firm evidence that ambulatory blood pressure measurement is a more sensitive predictor of cardiovascular outcome than conventional measurement.6 We have not considered the complex issues of health economics that the increasing use of ambulatory measurement raises.7 We realise that this technique is being used more often and that doctors who find ambulatory measurement useful in the day to day management of patients with high blood pressure need recommendations from those who have experience. However, regardless of the technique used to diagnose hypertension it is only one factor in determining a patient's risk profile and must be assessed in relation to concomitant disease, …