Radical Dharma and Eco-Dharma represent two critical movements in contemporary American Buddhism. While Radical Dharma frames spiritual liberation as inseparable from collective social liberation and racial justice, Eco-Dharma frames spiritual liberation as inseparable from ecological care. Both movements draw heavily on Mahāyāna (and especially Zen) Buddhism. However, there are also rich roots for radical social and ecological engagement grounded in early Buddhist teachings. In this course we will explore these roots, and trace their growth in the modern development of socially and ecologically engaged Buddhism in South and Southeast Asia. We will focus especially on the engaged work of B.R. Ambedkar, Buddhadasa Bhikkhu, Sulak Sivarksa, A.T. Ariyaratne and Thich Nhat Hanh, attending to their interpretations of early Buddhist teachings in particular. To help contextualize these figures and movements, a few sessions will outline the broader history of socially engaged Buddhism, and major figures and theories in the development of Mahāyāna approaches to engaged Buddhism.