This paper reviews the evidence regarding the cardioprotective effects of oestrogen replacement therapy in postmenopausal women. Oestrogens have been shown to improve serum lipid profiles, carbohydrate metabolism, and insulin sensitivity; prevent the formation and development of atherosclerotic plaque; reduce blood pressure and plasma fibrinogen levels; and favourably affect overall cardiac function. Thus, oestrogen replacement therapy may prevent or inhibit the progression of existing coronary disease, and may also have a protective effect against acute cardiovascular and cerebrovascular ischaemic events.