Different interpretations of what constitutes "trash" can reveal complex interactions between Tibetans and Han Chinese in the Eastern Himalayas. This article adopts the term "trash talk" to illuminate how the Tibetan practice of depositing garments as offerings to sacred mountains has become a center of Tibetan-Han debates about ethnic identity, morality, and personhood. Establishing the contours of waste-management infrastructure in a Tibetan area of Yunnan, China, that has been developed for tourism, this article examines the Tibetan term dreg pa དྲེག་པ(pollution), a morally laden notion of impurity. The author highlights how Tibetans seek to avoid dreg pa and achieve a reciprocal balance with "mountain-persons" (mountains as sacred beings) by making offerings of personal garments. The Han Chinese waste-management sector's perception of these garment offerings as litter creates a dispute between Tibetans and Han as to what is sacred and what is trash. Drawing on field research, the author argues that the offered garments should be seen not as trash but as people—active entities that mediate the reciprocal relationship between humans and the environment. Further analysis of the experience of two Tibetan informants reveals how the issue of used garments and dreg pa can even form a basis for personal transformation and the reinvention of personhood. These linkages among the local notion of dreg pa, uncertainties surrounding used garments, and personhood suggest that waste-management policies must take local notions of waste into consideration in order to be both efficient and culturally sensitive, especially in the current troubled trash politics of mass tourism and global environmentalism.