For symptomatic stenosis of the carotid artery the invasive options for treatment (by means of stent or operation) are superior to conservative medical treatment. Recent multi-center randomized controlled trials, which will be presented here, indicate that stenting in the treatment of symptomatic carotid stenosis is neither safer nor more effective than carotid endarterectomy. When carried out by an experienced interventionalist stent-assisted angioplasty (CAS) is an alternative to carotid endarterectomy. Subgroup-analysis indicates that for patients older than 70 years of age invasive techniques should be the method of choice. In the case of contralateral high-grade stenosis or occlusion, CAS is the method of choice. For patients treated by stenting, the periprocedural complication rate is not influenced by the use of protection systems. The present results on symptomatic carotid stenosis should not be transferred to the therapy of asymptomatic carotid stenosis. A 3-armed study (SPACE2) on the comparison of the best medical treatment with the invasive treatment modalities (CAS or CEA) is in preparation and will be started in 2 months.