Despite improvement in the early outcome for patients undergoing complete repair of atrioventricular septal defects with a common atrioventricular orifice, the incidence of reoperation for failure of the repair of the left atrioventricular valve remains high. The surgical techniques employed in our most recent experience, including routine suture of the septal commissure and liberal use of valvar annuloplasty, were successful in achieving a very satisfactory competence of left atrioventricular valve with a iow incidence of reoperation for failure of the repair.