For many years, Leanne Betasamosake Simpson took solace in skiing—in all kinds of weather, on all kinds of snow across all kinds of terrain, often following the trail beside a beloved creek near her home. Recently, as she skied on this path against the backdrop of uncertainty, environmental devastation, rising authoritarianism and ongoing social injustice, her mind turned to the water in the creek and an elemental question: What might it mean to truly listen to water? To know water? To exist with and alongside water? So began a quest to understand her people’s historical, cultural, and ongoing interactions with water in all its forms (ice, snow, rain, perspiration, breath). Pulling together these threads, Leanne began to see how a “Theory of Water” might suggest a radical rethinking of relationships between beings and forces in the world today. In this inventive work, Simpson draws on Nishnaabeg origin stories while artfully weaving the work of influential writers and artists alongside her personal memories and experience—and in doing so, reimagines water as a catalyst for radical transformation, capable of birthing a new world. Theory of Water is a resonant exploration of an intricate, multi-layered relationship with the most abundant element on our planet—one that, as Simpson eloquently shows, is shaping our present even as it demands a radical rethinking of how we might achieve a just future.