An assessment of Martin Heidegger’s notion of releasement (Gelassenheit) is essential due to former misconceptions concerning its applicability for environmental ethics. Recent material on Heidegger is bringing new interest in the practical applicability of Gelassenheit for eco- phenomenology. This book examines the claims of secondary literature, both positive and negative, and compares that with Heidegger’s Gelassenheit (1959), translated as Discourse on Thinking. Gelassenheit, when viewed as a process rather than static, holds resources for environmental responsibility. Heidegger’s Gelassenheit gives us another understanding of our relation to nature, a self-emerging relation that is non-objectified. Gelassenheit offers the field of eco-phenomenology an ethic that goes beyond the subject-object dualism, a non instrumental ethic that holds potential for how to treat nature in the technological world in which we live. This book is addressed to Heidegger scholars, environmental ethicists, eco-phenomenologists, environmental scientists, environmental studies scholars, and continental philosophers.