Hypertension is a very prevalent condition which alone, or in association with various risk factors including smoking, hypercholesterolemia and diabetes mellitus, may lead to fatal or non-fatal stroke or myocardial infarction. Antihypertensive treatment is effective at preventing cardiovascular events. However, only a minority of patients with hypertension ever experience a stroke or myocardial infarction and a few patients with well-controlled hypertension may suffer such events. Before committing a patient to lifelong treatment, the physician should ensure that high blood pressure is not a symptom of an underlying correctable disease, that hypertension is persistent and requires medication, and that prevention measures take into account all correctable risk factors.