This book analyses the moral theory of the seventh century Indian Mahayana master, Santideva. Santideva is the author of the well-known religious poem the Bodhicaryavatara (Entering the Path of Enlightenment) , as well as the significant, but relatively overlooked, Siksasamuccaya (Compendium of Teachings) . Both of these works describe the nature and path of the bodhisattva, the altruistic spiritual ideal especially exalted in Mahayana literature. With particular focus on the Siksasamuccaya , this work offers a response to three questions: What is Santideva’s moral theory? How does it compare to other analyses of Buddhist ethics? Can one moral theory adequately describe Buddhist moral thought? An exegetical account of the bodhisattva path as outlined in the Siksasamuccaya is provided by textual analysis and translations. The central moral concept of this Buddhist thinker and Santideva’s ethical presuppositions and moral reasoning are brought to light by analysing the use of key moral terms and comparing them to other Buddhists’ principles. It is also considered in relation to dominant Western ethical theories. By focusing on a neglected Buddhist Sanskrit text by a major Mahayana figure, Barbra Clayton helps to redress a significant imbalance in the scholarship on Buddhist ethics, which has up to now focused primarily on the ethics of the Pali literature and as interpreted in the Theravada tradition.