The Downside Abbey library holds nearly 500,000 books and the Archive collections are equally vast. Materials include an 18th century cookbook, an 11th century book of prophets, many papal bulls, a photographic collection dating back to 1854, and a set of John Speed maps.
They consider their strengths to be in Theology, Philosophy, Patristics, Ecclesiastical History and general history studies. The collection is eclectic and whilst their strengths are primarily suited to complement the studies of their monks, successive Monk Librarians have built up collections that mark them out as one of the finest Monastic Libraries in Europe. Their earliest texts date back to the eleventh century and they have a rich collection of Incunabula and late-Medieval/Early Modern manuscript books. The collections are both sacred and profane and reflect the wide interests of the Monastic Community and their European heritage.