This textbook offers a reasoned and accessible introduction to the philosophy of the environment and the current environmental crisis, designed for scholars and students in both philosophy and the natural and environmental sciences.The volume addresses the history and meanings of the concept of "environment", provides a theory of the relation between living beings and their environments, and tackles a wide spectrum of key philosophical issues related to the environment and the environmental crisis in a straightforward framework and accessible style. The book’s unique approach to environmental philosophy addresses the environment of all living beings and extends beyond environmental ethics to include conceptual history and analysis together with insights from evolutionary and developmental biology, ecology, and environmental and conservation sciences. The book consists of five chapters, each built around a specific thesis drawing upon philosophers and concepts including George Canguilhem, Rachel Carson, Donna Haraway, Lamarck’s and Darwin's evolutionary theories, Humboldt’s theory of nature, and the Gaia hypothesis. The final chapter introduces topics such as environmental denialism and post-natural environmentalism as conceptual tools for better understanding the current ecological crisis.Targeted at students and scholars in both philosophy and the environmental and life sciences, the book distinguishes itself through its approachable style and choice of topics, which are also well suited to junior researchers who seek to better understand the current environmental crisis.