Animals in International Law. By Anne Peters. The Hague, Netherlands: Brill|Nijhoff, 2021. P. 641. Index.

sometimes nicely tucked away in a footnote— the reader should not be daunted by the book’s size nor shy away from reading it cover to cover. She will then discover that the book is a veritable trove of intellectual pleasure, full of ideas and written in a remarkably accessible style. She will also discover, and maybe deplore, that aside from the brief introduction and conclusion, and altogether very rare discursive interventions in between, Koskenniemi gives relatively little guidance in terms of making explicit connections between the authors, the ideas, the Chapters, and the Parts. He leaves the reader to think for herself. In doing so, he has issued an open invitation for further research and reflection on some grand topics that spring to mind, such as the genealogies of ideas, the comparison of national or regional approaches, the transnational debates between scholars from different countries, the role of shared ideas and values in international networks of diplomats and economic elites, and most ambitiously, a global approach to constitutional history. With this book, Koskenniemi has pioneered an integrated constitutional history of international order. He has set a high bar for those who want to follow on this path, but he has also offered strong foundations to build on.