The book covers the full range of international, regional and transnational courts and tribunals, with a focus on their treatment of the environment. Presented in three parts, the book addresses how individual courts and tribunals engage with environmental matters (Part I); compares the manners in which these courts and tribunals are resolving key issues common to environmental litigation (Part II); and delves into future opportunities and developments in the field (Part III). The book therefore serves as both an essential aid to scholars and students engaged in research in this ever-developing field, and practitioners involved in environmental litigation. The breadth of international courts and tribunals covered in this book can only be achieved through an edited volume: each contributor has brought their specialist knowledge and experience to the task of preparing their respective chapters.We, the editors, are deeply grateful for their commitment to the project—despite the delays and difficulties caused by the COVID-19 pandemic. We also extend our sincere gratitude to our assistant editor, Joseph Reeves,who has been instrumental in bringing the final manuscript together.