Arterial compliance as evaluated by three different indices (pulse wave velocity, pulse pressure stroke volume, and an exponential analysis of the diastolic pressure decay) was found to be abnormal in patients with established essential hypertension and particularly in elderly hypertensive patients. Two of the three indices reflected significantly impaired arterial compliance already in borderline hypertension. Age, systolic, and diastolic pressures evolved as independent determinants of pulse wave velocity. It is concluded that arterial compliance becomes impaired early in hypertensive cardiovascular disease at the time when arterial pressure is only to the borderline level. However, age per se seems to be the most predominant risk factor for systemic arterial disease.