The International Registry of Acute Aortic Dissection (IRAD) is a consortium of research centers evaluating the current management and outcomes of acute aortic dissection and intramural hematoma. It was established in 1996, and is comprised of 58 large referral centers in 13 countries. IRAD endeavors to assess the etiological factors, modes of presentation, clinical features, treatment, and hospital and post-discharge outcomes of patients with acute aortic dissection around the world.