Isolated systolic hypertension affects between 10 and 20% of the elderly population and carries a substantial risk of cardiovascular complications. As no prospective, randomized trials have produced scientific evidence of a treatment benefit in elderly patients with isolated systolic hypertension, opinion on when and how to treat this condition differs among expert committees as well as among individual doctors. This article reviews the present treatment policies in patients with isolated systolic hypertension. It describes the ongoing intervention studies that have been designed to examine the hypothesis that antihypertensive treatment confers a benefit to elderly patients with isolated systolic hypertension in terms of a reduced morbidity and mortality. The Syst-Eur trial, which was recently initiated by the European Working Party on High Blood Pressure in the Elderly, is described in greater detail.