The Petrine ministry has been at the center of the modern ecumenical discussion because it deals directly with the question of the unity of the church. The International Bridgettine Centre in Farfa, Sabina, has seriously undertaken a study of the theological, historical, and dogmatic issues that underlie the issues of Christian unity dealing with the role of unity as exercised by the Pope. This work represents part of the work in which the Centre has been engaged during these past ten years.