Like all the most important religious orders of the modern age, the Italian Congregation of the Foglianti also adopted specific legislation with regard to their libraries, awarding an educational and formative value to books and reading. It is in Rome, the city of the popes, that the most important Italian Foglianti libraries are located, which in the 17th century went through their golden period. The paper focuses on the creation and development of the most important Roman Foglianti libraries: those of the monasteries of Santa Pudenziana, San Bernardo alle Terme and San Sebastiano alle catacombe.