This book develops and applies a new theoretical framework for thinking and reasoning about the purpose, value, and social implications of environmental protection policies. I rely most heavily on a particular theory of social justice—the “capabilities approach” advanced by Martha Nussbaum—to provide the framework’s guiding normative principle and basic conceptual logic. The capabilities approach has much in common with rights-based approaches to evaluating and designing policies because it treats individual-level political protections as constitutional guarantees owed to citizens living in liberal democratic societies. The individualistic focus has particular advantages for addressing the inequitable impacts that environmental policies produce, such as those that expose people to different levels of environmental harm. The approach to designing and evaluating environmental policy that I develop treats a certain level of environmental quality as an entitlement to which each individual citizen has a basic political guarantee. However, I define this individual guarantee in terms of a person’s capabilities rather than a person’s rights. As a conception of individual well-being and advantage, people’s capabilities are preferable to rights, most simply, because the former defines a sphere of action that rights commonly protect, as well as the preconditions that make it possible for people to engage in specific forms of protected action. By extending the account of what is worthy of political protection to include these enabling conditions I hope to advance an evaluative framework that clarifies and reveals the vital role the natural environment plays in a meaningful and flourishing human life, and therefore to affirm environmental quality as a matter of basic political protection. Environmental policy gives rise to many different kinds of questions. Those that motivate the present project concern issues of valuation, justification, and participation. How should we value the natural environment when we assess the social value of policies that protect it? On what theA?oretical and philosophical basis should we seek to justify environmental protection? What role should citizens, experts, and various other stakeholders play in environmental policy decisions? Because my intent is to bring a particular theoretical approach to justice to bear on answering these questions, this book is an exercise of applied political theory.