Creator's Description: This essay is a study of the corpus of texts associated with the Vinayasūtra, written by ninth-century Indian scholar Guṇaprabha, and included in the Tibetan Bstan 'gyur. The essay begins with consideration of the sūtra format of the texts, the myths associated with the author, and continues to examine the Indian and Chinese Vinayas available to the Tibetans and their choice of the Mūlasarvāstivāda and Guṇaprabha's Vinayasūtra corpus. These are followed with a brief discussion of the problems of manuscript availability and translation into Tibetan. The essay concludes with a brief review of the texts and their translators. The Tibetans' choice of these texts as core documents for Tibetan Buddhism is relevant to the study of canon formation, to the institutionalization of monasticism, the place of monastic life in Tibetan Buddhism in relation to philosophical inquiry and tantric ritual, and to the Tibetans' preference for Indian sources.