The anomalous aortic origin of a coronary artery from the wrong sinus of Valsalva with interarterial, intramural, and/or intraconal course is a rare congenital anomaly that is associated with a high risk of sudden death in children. The Congenital Heart Surgeons’ Society established the Registry of Anomalous Aortic Origin of the Coronary Artery to help determine the outcome of children and young adults managed with surgical intervention versus observation and to test the hypothesis that subsets of patients with anomalous aortic origin of a coronary artery can be identified in whom the risk of intervention is less than the risk of observation. All institutional members of the Congenital Heart Surgeons’ Society were recruited for participation. The registry consists of a retrospective cohort of patients diagnosed between 1 January, 1998 and 20 January, 2009 and a prospective, population-based cohort of patients newly diagnosed from 21 January, 2009 onwards. Baseline demographics, diagnoses, and results of tests will be obtained through a review of the medical records. Annual follow-up data will be collected. Data will be analysed for different factors of risk at diagnosis, different strategies of treatment, and the impact of both on the outcomes of the patients. As of June 2010, 28 institutions had applied for approval from their institutional review board and 16 institutions had received approval from their institutional review board. Seventy-four patients have enrolled to date. We hope to use the established Pediatric Cardiomyopathy Registry as a guide to successful implementation, with a cooperative effort between institutions. The overall purpose of the Registry of Anomalous Aortic Origin of the Coronary Artery is to determine the outcome of surgical intervention versus observation in children and young adults with anomalous aortic origin of a coronary artery, and to describe the natural and “unnatural” history of these patients over the course of their lifetime. In this report, we describe the creation and design of the Registry of Anomalous Aortic Origin of the Coronary Artery. Data from the registry will be published at a later date.