Lowering blood pressure by medical treatment is not enough for correct prevention of the cardiovascular complications of high blood pressure. In this respect, we would like to emphasize the potential value of the non-antihypertensive effects of angiotensin-converting enzyme (ACE) inhibitors which may be summarized as follows. In the heart, ACE inhibitors significantly reduce left ventricular hypertrophy. They have no noticeable anti-ischaemic activity and are devoid of antiarrhythmic effects. On the kidneys, ACE inhibitors seem to have a protective effect, still to be determined, in certain cases of diabetes or renal impairment. ACE inhibitors have no deleterious metabolic effects. Other antihypertensive agents share the same properties. Long-term comparative trials are necessary to find out whether some of these drugs are more effective in this field than the others.