Recent prospective epidemiologic studies have directed attention to systolic blood pressure (SBP) as a better guide than diastolic blood pressure (DBP) to evaluate cardiovascular and all mortality, and recent data have underlined the importance of pulse pressure (PP) as an independent cardiovascular (CV) risk factors(5-7) in individuals more than 50 years of age. Furthermore, it has been shown that drug treatment of hypertension frequently results in adequate control of DBP, whereas control of SBP is achieved to a significantly smaller extent. Such studies have focused attention on the factors that determine the level of SBP and PP. Systolic blood pressure results from the interaction of three principal factors: 1) characteristics of left ventricular ejection (stroke volume); 2) cushioning (dampening) function of the large arteries (arterial stiffness); and 3) propagative and reflective properties of the arterial tree (intensity of wave reflections and timing of incident and reflected pressure waves). Considering the different mechanisms associated with increased SBP, individualized therapeutic approaches will require knowledge of the patient's unique profile of arterial stiffness and wave reflection characteristics. (C) 2005 American Journal of Hypertension, Ltd.