The book offers an in-depth examination of the production, distribution, and use, from the late fifteenth century to the present, of the 74 editions ofBooks of Hours printed in Italy in the fifteenth century, 198 copies of whichhave survived. They are today in 82 libraries in 16 countries in Europe andNorth America. Special attention is paid to the transmission of the texts inprint, their stemma editionum, the cycle of illustrations, and the identificationof buyers and users, including the question of the price of these first printedcopies in comparison to that of contemporary manuscript copies. Viewingthis genre from the Middle Ages to the nineteenth century, the studycontextualizes the success of these editions over the long term and thephenomenon of the rapid replacement of older incunabula by newer editions.It probes the place of Books of Hours within the first printed provision ofliturgical books, the circulation of the Roman Use, the dissemination of theVenetian calendar in Italy and beyond, and looks also at the changes inspiredby the Council of Trent. The book includes a complete transcription of allthe calendars and 88 plates in colour.