The title of this book is somewhat deceiving. It sounds quite general, although its topic is actually very specific. The main topic of the book is the role of social learning in the use of environmental principles to form international environmental law. Yet the term ‘‘social learning’’ did not find its way into the title of the book, or even the back cover, despite its central role within the text of the book. The subtitle of the book would make a more appropriate main title, perhaps with a subtitle about social learning. While the purpose and premise of the book concern macro-level theories of international relations, the bulk of the text concerns a rather narrow slice of the wide topic addressed by the book’s title. Decidedly socially constructivist in its approach to international relations, this book addresses the social context in which international environmental laws are crafted. It does not address principles or their historical origins so much as it focuses on the ‘‘constructed nature of their function in international law and politics’’ (p. 22). Clearly adapted from a PhD dissertation, this book begins with literature reviews, moves on to defining and discussing the concept of an environmental principle and the role of social learning, and then looks at three case studies before the conclusion, in which numerous observations are made about the roles of environmental principles and social learning in the three case studies. The book does not focus on environmental principles themselves, but rather on their roles and functions in influencing governance and change more generally. There are a few sample listings of environmental principles from other works, and some of these principles are discussed briefly as they come up in the case studies, but this is done for the purpose of drawing out how and why these principles were used more than an examination of the principles themselves or their merits. There is more discussion of social learning than discussion of principles. The chapter on ‘‘function and role of environmental principles’’ is only 15 pages, while the chapters and sections on social learning span over 50 pages of the book. The chapter on ‘‘environmental principles as abstract or open-textured norms’’ has to do with the nature and definition of a principle and is sandwiched by chapters on ‘‘social learning at the international level’’ and ‘‘abstract and open-textured norms and social learning.’’