The results of a good deal of large epidemiological studies carried out in the last 3 decades clearly showed that moderate and severe arterial hypertension is a mayor risk factor for cardiovascular disease. At variance, mild hypertension was generally regarded as a more benign condition, if not associated with other risk factors. Recently, the attention of several investigators was focussed to identifying possible additional risk factors, which are related to high blood pressure, and might increase substantially the risk of mild blood pressure elevation. Left ventricular hypertrophy, activation of the renin-angiotensin system and a generalized increase in the Na+/Li+ countertransport are some of the factors that are implicated in hypertensive cardiovascular disease. Since not all available antihypertensive agents positively influence these factors, these observations could have not only pathophysiological and clinical, but also therapeutic consequences.