We evaluated the ability of real-time 3-dimensional (RT3D) echocardiography to diagnose congenital heart defects and its potential for presenting structural abnormalities in novel views. Seventy-five patients with suspected congenital heart defects were examined with the use of RT3D echocardiography. Images were reviewed off-line as multiple slices of the raw data or as volume-rendered images by a blinded observer. Diagnoses made from blinded review of the RT3D images were compared with the clinical report of the 2D echocardiogram obtained at the same visit. Real-time 3D echocardiography identified all structural abnormalities except for small atrial septal defects in 2 patients and coronary artery anatomy in D-transposition of the great arteries. Less than 5 minutes were needed to acquire RT3D images in all cases, and sedation was never required. Unique region-oriented views obtained from the 3D data set can be acquired quickly and have the potential to enhance understanding of complex cardiac anatomy.