As much as one third of patients with arterial hypertension are treatment refractory as they do not reach sufficient blood pressure control despite antihypertensive combination therapy of significant duration. In patients with therapy-resistant hypertension, the kidneys play a central role as activator of the sympathetic nervous system. Sympathetic nervous activation via efferent nerve fibers lying in the adventitia of the renal arteries leads to increased Na(+) reabsorption, increased renin secretion and reduction of renal plasma flow. Via afferent sympathetic fibers in the dorsal root of the spinal chord, the kidneys induce a further augmentation of central sympathetic nervous activity. With the method of renal sympathetic denervation (RSD) an interventional minimally invasive procedure has become available to precisely ablate afferent and efferent sympathetic nervous fibers surrounding the renal artery. Via an ablation catheter with an electrode tip and a radiofrequency generator a series of 4-6 ablation sites are administered in both renal arteries leading to denervation of the sympathetic nerve fibers while keeping the renal artery intact. Recent studies showed a significant and continuous reduction of blood pressure of 25-30 mmHg systolic and 10-15 mmHg diastolic for at least 2 years. Concerning the role of elevated sympathetic nervous system activity in forms of hypertension associated with other disorders, further applications of the procedure appear possible, although these are of a rather speculative nature at this time. The current mainstay of therapy-refractive hypertension is RSD, which is well supported by recent clinical data.