The Vatican Library has one of the most famous collections of Syriac manuscripts in Europe. These two volumes, written by members of the Assemani family intimately familiar with the collection, cover the Vatican Syriac manuscripts and Arabic manuscripts written in Syriac letters (i.e. Garshuni). Each manuscript is described (in Latin) in terms of script, size, and provenance; detailed lists of each manuscript’s contents are given, as well as explicits and scribal notes. The Garshuni manuscripts are described in the last part of the two volumes, and the set concludes with an index of writers and their works. This fundamental resource is absolutely necessary for readers interested in Syriac and Christian Arabic literature and Christianity in the middle east.