A new extensive operative technique with several points of important surgical significance was applied to six patients with a single or common ventricle in whom the types of anomalies consisted of common ventricle, Van Praagh's type C, in one instance and single ventricle, Van Praagh's type A and B, in five instances. The important points of this technique are an atrial approach designed to avoid damage to the ventricular function; reconstruction of the ventricular septum using a pouch graft with specially tailored, substitute Dacron vessels; adequate positioning of the prosthetic septum, resulting from use of a pouch graft; special consideration given to suturing at the site of attachment of the interatrial and interventricular septum to lessen damage to the conduction system, and double valve replacement. The adequacy of such extensive surgical repairs cannot be judged accurately until more patients are operated upon.