Resistant hypertension is defined by a blood pressure of at least 140/90 mmHg despite treatment with full doses or maximum tolerated doses of at least three antihypertensive medications, including a diuretic. Data, especially controlled trials on the prevalence of resistant hypertension are rare. Patients with resistant hypertension exhibit more end-organ target damage and have a substantial higher long-term cardiovascular risk than patients whose blood pressure is controlled. The development of heart failure, stroke, myocardial infarction, and renal failure are related to the degree of the elevation in blood pressure. In the lecture I will talk about pathophysiological aspects as well as treatment strategies.