Stress echocardiography has become a valuable technique for the non-invasive detection of coronary artery disease. Its accuracy has been shown to be superior to that of the exercise electrocardiogram and comparable to that of myocardial perfusion imaging. The adequacy of stress echocardiography with conventional two-dimensional imaging, however, is highly dependent on operator expertise. Further, interpretation of test results is subjective and qualitative, and is based on analysis of wall motion after arbitrary segmentation of the left ventricle. Real time 3-dimensional (RT3D) echocardiography is a new technique that permits the unrestricted assessment of left ventricular wall motion and function in a single cardiac beat without ECG or respiratory gating. We hypothesize that RT3D echocardiography will have similar or greater accuracy for the detection of wall motion abnormalities compared to the conventional two-dimensional examination. We therefore propose to acquire RT3D echocardiographic images in patients with known or suspected coronary artery disease who undergo stress echocardiography. We will correlate these results with findings from coronary angiography and compare the ability of RT3D echocardiography to detect coronary artery disease with that of the conventional two-dimensional exam.