The Sanskrit prātimokṣa-sūtras contained in the Gilgit Buddhist manuscripts have been identified as belonging to the Mūlasarvāstivāda school. However, the identification of these manuscripts as Mūlasarvāstivādin texts is problematic. A key factor for determining the school affiliation of a prātimokṣa is the rule order. The Gilgit prātimokṣa-sūtras, however, differ in their rule order. In this thesis, I explore the relationship of these Gilgit prātimokṣa-sūtras to Mūlasarvāstivādin literature. In order to do so, I have conducted a comparative analysis of the Gilgit prātimokṣa-sūtras focusing on differences in rule order in Gilgit Serials 2, 3a, and 4b/4c. I have also compared the rule order contained within the Gilgit prātimokṣa-sūtras to known Mūlasarvāstivādin commentaries. I argue that we have evidence for two distinct Mūlasarvāstivādin Vinaya traditions within the Gilgit prātimokṣa-sūtras. The author(s)/redactor(s) of Gilgit prātimokṣa-sūtras 2 and 3a were aware of a tradition similar, if not identical, to that known to the author(s)/redactor(s) of the Mūlasarvāstivādin prātimokṣa-sūtra contained in the Tibetan canon. Serial 4b/4c contains a different Mūlasarvāstivādin Vinaya tradition, one that has close parallels to Mūlasarvāstivādin commentaries. The Gilgit prātimokṣa-sūtras, therefore, contain Sanskrit evidence for multiple Mūlasarvāstivādin Vinaya traditions. / Master of Arts (MA)