Cilazapril is a new nonthiol group containing angiotensin converting enzyme (ACE) inhibitor, which was designed by a computer-modelling technique in order to obtain a compound with high specificity and selectivity for the target enzyme. Cilazapril has been investigated in more than 4000 patients with all degrees of hypertension, as well as in the special patient groups such as the elderly, renally impaired, and patients with concomitant diseases, such as congestive cardiac failure or chronic obstructive pulmonary disease. In these studies, the blood pressure-lowering effect of a single daily dose has been clearly established. The tolerability profile is similar to other frequently prescribed antihypertensive drugs, such as sustained-release propranolol, enalapril, captopril, atenolol and hydrochlorothiazide. Recently, investigations have revealed that cilazapril, in addition to its blood pressure-lowering abilities, can moderate the proliferative response seen in vessels after vascular injury caused by techniques such as ballooning. Clinical studies to verify these findings are currently ongoing.