Neither the role of surgery in Ebstein's anaomaly nor the surgical procedure of choice for its correction are clearly defined. Whether or not the artrialized right ventricle, which plays a major role in the functional abnormalities, should be obliterated in all cases remains unresolved. Of the 26 patients with Ebstein's anomaly seen at the University Hospital between 1953 and 1975, four were treated surgically at this center. All had closure of the atrial septal defect, reconstruction of a tricuspid annulus in the normal position, and insertion of a tricuspid prosthesis and an epicardial ventricular pacemaker. The two patients who also had the atrialized chamber obliterated improved dramatically. Thus, obliteration of the atrialized right ventricle appears to be associated with a better operative result.