"This edited volume finds its origin in a conference on the theory and practice of customary international law (CIL) and its interpretation, held in May 2019 at the University of Groningen. The conference was co-organized by the TRICI-Law project and the Interest Group on International Legal Theory and Philosophy (IGILTP)."--ECIP Preface.

Includes bibliographical references and index.

Between pragmatism and disenchantments : the theory of customary international law after the ILC Project / Jörg Kammerhofer -- The custom-making moment in customary international law / Jean d'Aspremont -- Misinterpreting customary international law : corrupt pedigree or self-fulfilling prophecy? / Noora Arajärvi -- The logic of absence in customary international law : an open-system approach / Anna Irene Baka -- Schrödinger's custom : implications of identification on the interpretation of customary international law / Markus P. Beham -- The significance of state consent for the legitimate authority of customary international law / Andreas Føllesdal -- Custom and the regulation of 'the sources of international law' / Diego Mejía-Lemos -- The ILC's new way of codifying international law, the motives behind it, and the interpretive approach best suited to it / Luigi Crema -- Beyond formalism : reviving the legacy of sir henry Maine for customary international law / Andreas Hadjigeorgiou -- Enkapsis and the development of customary international law : an encyclopedic approach to inter-legality / Romel Regalado Bagares -- Customary international law in the reasoning of international courts and tribunals / Vladyslav Lanovoy -- Eureka! On courts' discretion in 'ascertaining' rules of customary international law / Letizia Lo Giacco -- Identification of and resort to customary international law by the WTO appellate body / Mariana Clara De Andrade -- The practice of non-state armed groups and the formation of customary international humanitarian law : towards direct relevance? / Zhuo Liang -- Identifying custom in universal periodic review recommendations / Frederick Cowell -- Interpreting customary international law : you'll never walk alone / Panos Merkouris -- Practical reasoning and interpretation of customary international law / Kostiantyn Gorobets -- Different strings of the same harp : interpretation of rules of customary international law, their identification and treaty interpretation / Marina Fortuna -- Customary international law : identification v interpretation / Riccardo Di Marco -- 'And in the darkness bind them' : hand-waving, bootstrapping, and the interpretation of customary international law after / Chagos John R Morss and Emily Forbes -- The role of domestic courts in the interpretation of customary international law : how can we learn from domestic interpretive practices? / Nina Mileva -- Customary international law interpretation : the role of domestic courts / Cedric Ryngaert -- The relevance of customary international law in the domestic legal order of a federal state / Gerhard Hoogers.