In the past, coronary arterial anomalies have been difficult to diagnose by non-invasive methods. Identification of coronary arterial origins is now a routine part of the standard paediatric echocardiogram. Anomalous origin of a coronary artery from the pulmonary trunk is an extremely important diagnosis to make. Many echocardiographic features are not directly related to the visualisation of the coronary arterial origin. Left ventricular dilation and abnormal ventricular performance are common, along with mitral regurgitation and evidence of collateralisation of the flow from the coronary artery that has an aortic origin. In some cases, the anomalous coronary artery can be seen to arise directly from the pulmonary trunk. Congenital atresia of the main stem of the left coronary artery has a similar echocardiographic presentation, except that its aortic origin is not determined. Anomalous aortic origin of the coronary artery has important implications, as the first presenting symptom can be sudden death. With meticulous attention to the origins of the coronary arteries, echocardiographic diagnosis can also be achieved. In contrast to the anomalous origin of a coronary artery from the pulmonary trunk, ventricular performance is usually normal. Whenever there is doubt as to the definition of the origin of the coronary arteries and, indeed, when there is serious clinical concern that a coronary artery has an anomalous origin, other testing, such as cine-computed tomography, magnetic resonance imaging, or cardiac catheterisation may be indicated for confirmation or to provide greater anatomic detail.