Carotid artery disease is the most frequently identified cause of ischemic stroke and is mostly due to atherosclerotic disease. Landmark trials have demonstrated that surgical intervention in cases of high-grade carotid stenosis can reduce the risk of subsequent stroke. Endovascular approaches continue to be evaluated in ongoing trials. Careful patient selection is critical if the potential benefits of carotid revascularization are to be realized. Ultrasound is a safe, accurate, readily available method to evaluate carotid artery disease. The degree of stenosis is the parameter most frequently used to make decisions about therapeutic approaches. Plaque characteristics may also be useful for identifying high-risk patients. Microembolic signals detected by transcranial Doppler ultrasound can identify cerebral embolization before or after carotid intervention. This review discusses the current clinical role of carotid ultrasound in the selection of patients for the two most frequently used carotid interventions: carotid endarterectomy or carotid angioplasty and stenting.