Every year more than 250,000 patients suffer from ischemic (80%) or hemorragic (20%) stroke. Some 40,000 of these strokes are induced by stenosis or occlusion of the extracranial carotid artery. Several randomized studies (NASCET, ECST, ACAS, etc.) have proved that operative removal of high-grade carotid stenoses is an effective method in the primary and secondary prophylaxis of ischemic stroke. Operative therapy is significantly better than medical therapy with thrombocyte aggregation inhibitors. The prerequisite for effective operative prophylaxis is a low perioperative stroke rate. Even though the prophylactic value of carotid thrombarterectomy (TEA) is obvious, only about 5% of all carotid-related strokes are prevented by this operation. Essential conditions for increased efficiency in carotid surgery are close cooperation with the neurologist and the internist, screening of patients with a high risk for ischemic stroke, sophisticated, mainly non-invasive diagnostics, and more operative capacity. Interventional methods (stent, PTA) have not yet been proved safe and effective. These methods should be employed only in special cases after interdisciplinary discussions or in randomized studies.