This volume presents the explanations found in Tsong-kha-pa's Medium-Length Exposition of the Stages of the Path and in a commentary Tsong-kha-pa supplied for Chandrakirti's supplement to Nagarjuna's Treatise on the Middle, contrasting them with views of his predecessor Dol-bo-ba Shay-rab Gyel-tsen (1292-1391), as found in Dol-bo-ba's Mountain Doctrine. The two systems--Dol-bo-ba's doctrine of other-emptiness and Tsong-kha-pa's doctrine of self emptiness--emerge more clearly, contributing to a fuller picture of reality as viewed in Tibetan Buddhism.