Between 1960 and 1965 Gio Ponti worked on the headquarters of the religious congregation Notre Dame de Sion, located on the Janiculum Hill in Rome. His contribution to the project has been unidentified until recently. In 2014, the building was converted to house the Catholic University of America and the Australian Catholic University. This occasion gave architects of AeV Architetti the opportunity to carry out historical and archival research on the original project, the results of which are presented here. The book is enriched with the addition of detailed original drawings of the furnishings that still exist 50 years after the building was designed. Text in English and Italian.