RT Article T1 L'organizzazione dell'insegnamento alla Gregoriana prima del 1773 JF Gregorianum VO 85 IS 1 SP 113 OP 131 A1 Fois, Mario LA Italian PB Ed. Pontificia Univ. Gregoriana YR 2004 UL https://ixtheo.de/Record/1789386411 AB This contribution sketches the path that St. Ignatius traversed from excluding in 1541 educational work as a Jesuit ministry to his decision to found colleges and universities as apostolic woks of the Society for the formation of young lay students. Ignatius determined in 1553 that the Collegio Romano should be marked by universality in its make-up and outreach, and furthermore should exercise influence on the other colleges of the Society in Europe. From these beginnings, a comprehensive instructional program emerged in the definitive Ratio studiorum of 1599. We relate the organisation of the courses in literature and in the Faculty of Philosophy, which included pure and applied mathematics. The Faculty of Theology included a course on casus conscientiae or moral theology, and in the 18th century it added chairs of Canon Law, Church History, and Liturgy. In conclusion this article describes the three public «academies» founded for the intellectual and religious formation of select groups of students. Also, we tell of the instruction given in the exact sciences, with mention of some of more famous professors.