Ultrasound (US) techniques increase the ability of neurologists specializing in stroke to rapidly evaluate stroke patients, determine likely mechanisms of brain ischemia, determine arterial patency, quantify stenosis severity, and determine the most appropriate clinical management. Furthermore, the development of new US techniques based on the detection of US contrast agents may permit the evaluation of cerebral microcirculation and the identification of regions of angiogenesis, inflammation and thrombus during brain ischemia.