Domestic courts are among international law’s most effective conduits, and their role is growing. Those notions are now well documented, we have little systematic understanding of the methods these courts use to interpret international law. International law scholars have for decades considered how different legal systems approach international law differently, but interest in comparative research programs on international law has grown in recent years. Professors Helmut Aust and Georg Nolte’s edited volume,The Interpretation of International Law by Domestic Courts, fits squarely within this growing comparative international law agenda. The book sets out to evaluate the growing role that national courts play in the application and interpretation of international law. It features seventeen contributions by scholars and practitioners, including several members of the United Nations International Law Commission. The eighteen contributors hail from four continents, producing a diverse set of chapters and perspectives.

As some have noted recently, the study of the comparative dimensions of international law extends beyond domestic courts’ interpretation of international law alone; much of the foundation for domestic treaty interpretation occurs within the executive and legislative branches.

Yet judicial interpretations are particularly authoritative, as they are typically legally binding and often have domestic—and sometimes persuasive transnational—precedential value. Moreover, courts may be relatively “faithful agents” of the international legal order, especially vis-à-vis other branches; that is, they may have greater incentives to promote interpretive uniformity with regard to international law. For these reasons, a special focus on courts is worthwhile, and a volume on domestic courts’ interpretative processes for international law is a welcome addition to the comparative international law literature.

Kevin Cope & Mila Versteeg, Review of <em>The Interpretation of International Law by Domestic Courts</em> (reviewing Helmut Philipp Aust & Georg Nolte, The Interpretation of International Law by Domestic Courts: Uniformity, Diversity Convergence) 111 American Journal of International Law 538–544 (2016).