As a result of human activities, many organisms on Earth face serious and worsening threats to their continued existence. This is usually regarded as a matter of concern because maintaining a healthy non-human environment affects the well-being of humans. A Theory of Ecological Justice adopts a very different approach, defending in detail the claim that all organisms, sentient and non-sentient, have a claim in justice to a fair share of the planet’s environmental resources. Baxter puts forward a detailed argument for accepting that all organisms count, morally-speaking, and not simply those which are sentient, or those which human beings like or find useful. He explores the nature of justice claims as applied to organisms of various degrees of complexity and connects the concept of ecological justice to standard liberal theories of justice, such as those found in the work of Rawls and Barry. Finally, he explores the possibilities for achieving ecological justice within current national and international institutional arrangements for biodiversity protection. He also seeks to vindicate a universalist approach to moral thinking against those, postmodernists and others, who favour a contextualist view. This book makes a thoroughly developed, ground-breaking case for ecological justice. It is an essential read for everyone interested in environmental politics and ethics.