Hypertension is widely treated by primary care physicians as well as by cardiologists and other specialists. Clinical progress is often monitored by blood pressure measurements and other routine evaluations, but more sophisticated approaches may be required to learn whether treatment is effectively protecting the heart, kidneys, and other susceptible areas. Outcome measures therefore involve quantification of short-term, intermediate and long-term clinical observations; and, in addition, assessment of overall effectiveness must take into account economic factors and the levels of satisfaction perceived by patients, physicians, and health plans.