Stroke is an ischemic event in 80% and hemorrhagic in 20%, which can be distinguished by computed tomography of the brain. Unfortunately, no routinely applicable therapy is available for stroke. Several thrombolysis studies are underway and their results will become available in the next few years. Hemodilution has been abandoned except for hematocrits above 50%. Calcium antagonists such as nimodipine reduce vascular spasms after subarachnoidal hemorrhage, but their administration after ischemic stroke is unsuccessful. A new experimental approach is offered by glutamate receptor antagonists, which may prevent cell damage induced by the excitatory amino acid glutamate. In the case of cardio-embolic stroke, heparin should be started after 48 hours. Hypertension should only be treated above values of 200/120 mm Hg, with short-acting intravenous drugs. Because of the limited therapeutic options for completed stroke, primary prevention (treatment of hypertension, anticoagulation for atrial fibrillation) and secondary prevention after transitory ischemic attacks (endarterectomy for carotid stenosis > 70%, aspirin) should be intensified.