The 50th of the Encyclical Populorum Progressio is an opportunity to reflect on the role of Paul VI in the Church and in the history of the 20Th century. The Reports of Carlo Cardia, Gianfranco Garancini and Giuliano Amato, analyze the thought and the action of Montini, reformer of the Church and Society. The Populorum Progressio is the arrival of this reform. The Report of Card. Renato Corti, analyzes the Encyclical Evangelii Nuntiandi and the strength of the Gospel on the way; while the final report of the Card. Pietro Parolin, retraces the reforming action of Paul VI in the Second Vatican Council and new Government of the Church. The volume also reproduces the Regards sent by Your Holiness Pope Francesco, from the President of the Republic Sergio Mattarella, and from other personalities of the civil and ecclesiastical institutions, which the messages of opening and closing of the Congress of the Card. James Michael Harvey and the Abbot Osb Rev.mo Dom Roberto Dotta. Closes the volume an appendix of Documents, Speeches and Homilies of Pope Paul VI and a selection of national and international press review of the Populurum progressio.