This book investigates how sustainability informs the universal principles used in domestic and international law. It calls for the acceptance of sustainability as a recognized legal principle which could be applied to the entire legal system rather than just environmental law and regardless of its international or domestic levels. To this end, the book makes a contribution to a theory of global law by discussing whether, as a universally shared concern, environmental protection and the principle of sustainability should contribute to the 'greening' of the fundamental principles of law and governance. The book will be a valuable resource for students, researchers and policy makers working in the areas of environmental law and governance.