Advances in transducer technology have made three-dimensional echocardiography feasible for routine use in the echocardiographic assessment of cardiovascular disease. Real-time three-dimensional echocardiography (RT3DE) has potential to be especially useful in the evaluation of patients with congenital heart disease, by providing a detailed assessment of complex morphologic abnormalities and the spatial relationships of intracardiac structures. In patients with congenital heart disease, the ability to accurately assess cardiac chamber volumes and ejection fraction is important for determining the timing of intervention. In this article, we review the published literature on the use of 3DE in the assessment of morphology, chamber volume, and function in patients with congenital heart disease, as well as the use of RT3DE to guide interventional procedures.