International Rules brings together exemplary works from the most prominent approaches to international rules of International Law and International Relations disciplines. Included are chapters on Natural Law, Legal Positivism, Classical Realism, the New Haven School, Institutionalism, Structural Realism, the New Stream, and Feminist Voices. Each of the eight chapters begins with a brief overview, offers a representative work or works, and concludes with a selected bibliography. From Hugo Grotius to David Kennedy, from George Kennan to Robert Keohane, the featured authors provide valuable insights into their common subject: international rules. Despite divergent methods and objectives, they address fundamentally the same questions: What is the nature of such rules? What is their purpose? How do they originate? What role, if any, do they play in politics? Framing the selections assembled are two original chapter-length essays. The first chapter of this volume assesses the prospects for interdisciplinary collaboration; the final one suggests a direction for future research.