We owe a great debt to many of our colleagues and students at the University of Denver Sturm College of Law and elsewhere for their contributions to this extensively revised 2nd edition of our treatise on International Environmental Law and Policy for the 21st Century. This undertaking to capture the developments in the field over the past decade since our 2003 edition would not have been possible without them. The law student research assistants, now almost all graduates and lawyers, who labored so long and well on this edition are (in alphabetical order) Nadav Aschner, Jonathan Bellish, Anne Bingert, Chris Conrad, Kristi Disney, Lara Griffith, Alexandra Haas, William Kent, Caitlin May, Teresa (Tessa) Mendez, Jonathan Murley, Julie Nichols, Megan Sheffer, Eric Subin, and Sandy Teixeira. Deserving very special thanks are our Dean, Martin (Marty) Katz, Senior Associate Dean for Academic Affairs Federico (Fred) Cheever, and Associate Dean for Faculty Scholarship Alan Chen for so generously encouraging and supporting our scholarship. We are truly fortunate to have had the assistance of the dedicated and skilled professional staff of the Sturm College of Law, including Joan Policastri, Foreign, Comparative, and International Law Librarian for DU Law’s Westminster Law Library; Diane Burkhardt, Faculty Research Liaison for the Library; Keri Grundstein, former Administrator of the International Legal Studies Program; and McKenzie Gaby, former Faculty Support Team Leader. Over the years, our students in International Law and International Environmental Law have added immensely to our understanding of this relatively new frontier in the International Law field. We indeed are grateful to them for their interest and concern for the health and well-being of the planet and for the inspiration they have given us.