Fr. John Kerr Locke, S.J., PhD, was born in Chicago in 1933. He became a Jesuit novitiate in 1951 while enrolled in studies at Loyola University, Chicago, graduating with a Masters degree in English from that institution. Having petitioned the Society of Jesus to join their mission in South Asia, he took up residence at the Jesuit Mission in Kathmandu, Nepal, in 1958 and rapidly developed a remarkable fluency in Nepali. He became a citizen of Nepal in 1976 and remained in the country for the rest of his long career. His first assignment in his new posting was as a teacher in the Jesuit-founded St. Xavier's Godavari School, south of Kathmandu, an institution in which he later served as principal from 1966-70. From 1970, Fr. Locke pursued graduate studies focused on the Newar Buddhist tradition at Tribhuvan University, Kathmandu, where he completed Masters and doctoral programs. Fr. Locke dedicated the rest of his life, some 50 years in total, to the study of Buddhist practice in the Kathmandu Valley, and was widely acknowledged as the leading scholar in this field. Aside from his prodigious efforts in his primary area of study, Fr. Locke also found time to fulfill several other roles, including continuing involvement in teaching and administration at the Godavari School, mentoring of numerous younger Western and Nepali scholars, providing advice to Catholic leadership on inter-religious matters and editing the scholarly journal, Kailash. He authored a number of books and papers on Newar Buddhism throughout his career, all of which were significant contributions to the field. The present volume, previously long out of print and unavailable, is considered his most important work.