Several studies and intervention trials performed during the past 30 years have provided evidence that hypertension-related cardiovascular risk is not irreversible. This is because the reduction in blood pressure (BP) induced by antihypertensive drugs has been shown to be accompanied by a clear-cut decrease in the rate of cardiovascular events and complications. There is also evidence that BP control in the population is far from being optimal, and that no more than one quarter of treated hypertensive patients display BP values <140/90 mm Hg. The reasons for inadequate BP control are multiple, involving a combination of factors such as inadequate compliance with treatment, intolerance to side effects of currently prescribed drugs, and insufficient clinical use of combination drug treatment. This article focuses on three major areas. It first provides an overview of the current status of BP control in treated hypertensive persons. It then examines the factors potentially responsible for this phenomenon, with particular emphasis on the relevance of the so-called "compliance factor." Finally it provides an overview of the tolerability and compliance profile of the angiotensin II receptor antagonists, a new class of antihypertensive drugs characterized by an efficacy and safety profile.