Perhaps the most difficult element in the traditional teaching on original sin is the claim that the very guilt of Adam's sin has been passed on to the entire race. It was Augustine who, in the course of the Pelagian controversy, first drew this conclusion from St. Paul's discussion of sin, particularly in the letter to the Romans. Augustine ultimately attributed the transmission to the agency of concupiscence, a less than happy solution. When he came to treat the issue in his Summa theologiae, Aquinas shifted the agency from the impetus of concupiscence to the will of the first man, a move of marked importance in the Augustinian tradition. But, as this paper will show, Aquinas was already anticipated in this by the approach taken by Anselm in his On the Virgin Conception and Original Sin.