This report details the two-dimensional echocardiographic assessment of 41 patients with Ebstein's anomaly. The anatomic spectrum of Ebstein's anomaly is correlated with surgical and autopsy observations in 66% of these patients. Morphologic abnormalities of the tricuspid valve and right heart structures were uniquely assessed by noninvasive two-dimensional echocardiographic examination. Features of the tricuspid valve that best related to decreased functional capacity were: 1) absence of the septal leaflet, and 2) pronounced tethering, restriction of motion and displacement of the anterior leaflet of the tricuspid valve. This 4 1/2 year experience suggests that two-dimensional echocardiography can replace angiography as the procedure of choice for diagnostic and morphologic assessment of Ebstein's anomaly. Cardiac catheterization is necessary only when specific hemodynamic questions or clinical inconsistencies exist.