Nothing is permanent. The idea of impermanence, or mi rtag pa, is a core idea in Tibetan Buddhism. Meditating on impermanence helps individuals comprehend the transitory nature of reality, and thus prepare for death. Grappling with this philosophical idea is the responsibility of Buddhist monks and nuns, whose lives are devoted to the practice of religion. But, as with all religious concepts, impermanence also shapes the lives and ideas of lay people in Tibetan society. For ordinary Tibetans, what does it mean to live impermanence, for this notion to ground your understanding of being and possibility? Specifically, if meditations on impermanence prepare one for death, can they also be useful for something less predictable, for the possibility of social death? In this lecture, I present the history of the controversial Pangdatsang family. In the span of one generation, they rose from being local leaders to the wealthiest and one of the most powerful families in all of Tibet. The story of their becoming is also that of their undoing. In the 1960s era of Tibetan exile and Chinese colonization, the family suffered a social death that still resounds today. This story of a family is also a political and ethnographic history of Tibet, offering insights into how mi rtag pa/impermanence as a lived concept, and not just as a philosophical ideal, is a strategy for addressing change at personal, national, and global levels.