The concept of obligations erga omnes - obligations to the international community as a whole - has fascinated international lawyers for decades, yet its precise implications remain unclear. This book assesses how this concept affects the enforcement of international law. It shows that all States are entitled to invoke obligations erga omnes in proceedings before the International Court of Justice, and to take countermeasures in response to serious erga omnes breaches. In addition, it suggests ways of identifying obligations that qualify as erga omnes. In order to sustain these results, the book conducts a thorough examination of international practice and jurisprudence as well as the recent work of the UN International Law Commission in the field of State responsibility. By so doing, it demonstrates that the erga omnes concept is solidly grounded in modern international law, and clarifies one of the central aspects of the international regime of law enforcement.

Because of its unique nature, the sources of international law are not always easy to identify and interpret. This book provides an ideal introduction to these sources for anyone needing to better understand where international law comes from. As well as looking at treaties and custom, the book will look at more modern and controversial sources.

This book examines an important unresolved question of current international law: the legal position of third-party countermeasures.

Actio Popularis before International Courts and Tribunals examines actio popularis in the context of the symbiotic relationship between procedural and substantive normativity in international law. Actio popularis is an important procedural tool devised to address the challenges posed by the relativization of substantive normativity and recognition of norms established to protect collective interests in international law. Farid Ahmadov’s analysis underlines the ineffectiveness of bipolar litigation in enforcement of collective obligations in international law and the importance of introducing new procedural mechanisms to address the challenges posed by the transition from bilateralist to multilateralist normativity. The volume highlights the subtle link between interpretation of standing rules and the ways in which judicial policy concerns inform decisions of international courts and tribunals on admissibility of actio popularis.

Peremptory Norms of General International Law (Jus Cogens): Disquisitions and Dispositions is a collection of contributions on various aspects of jus cogens in international law.

This Oxford Handbook examines the sources of international law, how the understanding of sources changed throughout the history of international law; how the main legal theories understood sources; the relationship between sources and the legitimacy of international law; and how sources differ across the various sub-areas of international law.

This book sets out to articulate a comprehensive theory of customary international law that can effectively resolve the conceptual and practical enigmas surrounding it. It takes a multidisciplinary approach and draws insights from international law, legal theory, political science, and game theory. It is anchored in a sophisticated ethical framework and explores the interrelationships between customary international law and ethics.