Carotid ultrasonography is a safe and available noninvasive diagnostic tool that provides information about the carotid arteries' characteristics and may be used for early detection of coronary artery disease as well as cardiovascular and stroke event risk stratifications. We performed a systematic search of articles discussing carotid ultrasonography in the English literature recorded in PubMed from 2010 to September 2012. Generally, the studies showed that internal carotid artery intima-media thickness is a more powerful variable than common carotid artery intima-media thickness. Moreover, the presence of carotid plaque and plaque volumes are more reliable and accurate estimators of coronary artery disease and risk of a stroke or cardiovascular event than intima-media thickness.