Large-scale end-point trials have demonstrated that antihypertensive treatment reverses the risk of stroke attributable to high blood pressure and probably reduces the incidence of myocardial infarction. Despite this major achievement in therapeutics, substantial goals still need to be achieved. Thus, there is a need for improvement in existing antihypertensive agents in terms of greater blood pressure-lowering efficacy and improved impact on coronary heart disease in younger subjects. There is also a pressing need for a reduction in adverse effects. The incidence of these far exceeds the potential benefit of treatment. Last, the costs of therapy are assuming growing importance in the face of tight financial constraints on health care systems throughout the world.