Women appear to be protected, until the menopause, from the development of coronary artery syndromes. This protective effect seems to be due to the beneficial effect of ovarian hormones, in particular oestrogens. A number of potential mechanisms for the protective effect of oestrogens have been proposed. An important postulated mechanism could be by improving the function of vascular endothelium. In this review, we present the currently published studies that have evaluated the effects of 17 beta-estradiol, the only oestrogen used in France for hormone replacement therapy, on peripheral and coronary vasomotor function in postmenopausal women.