This Critical Concepts series (a Routledge Major Work) is an anthology of　influential works on international law. The collection covers the　principal facets of both classical　and contemporary international law. In making their selection, J.H.H. Weiler and Alan T. Nissel consulted with a wide range of experts and chose those pieces that in their view both shaped the field and have illuminated its contours. These articles have, or are expected to have, considerable "staying power."
By juxtaposing classical with more contemporary articles, this anthology illustrates the motion of international　law—the evolution of doctrine, practice and historiography of the field. The series begins with a consideration of the fundamental systemic (Volume I) and　conceptual (Volumes II and III ) features of International Law. It then maps out substantive aspects (Volumes IV and V). The collection concludes (Volume VI) with what the authors call "multi-inter-disciplinary" approaches to the field.