The book gathers the general report and the national reports presented at the XXth General Congress of the IACL, in Fukuoka (Japan), on the topic ¿Debating legal pluralism and constitutionalism: new trajectories for legal theory in the global age¿. Discussing the major contemporary changes occurring in and problems faced by domestic legal systems in the global age, the book describes how and to what extent these trends affect domestic legal orderings and practices, and challenges the traditional theoretical lenses that are offered to tackle them: constitutionalism and pluralism. Combining comparative law and comparative legal doctrine, and drawing on the national contributions, the general report concludes that most of the classic tools offered by legal doctrine are not appropriate to address most of today¿s practical and theoretical global legal challenges, and as such, the book also offers new intellectual tools for the global age.

General Report - Debating legal pluralism and constitutionalism: new trajectories for legal theory in the global age.- A particular dialogue between systems. The Argentinian case.- Reconciling legal pluralism and constitutionalism: New Trajectories for legal theory in the age of globalism in Botswana.- Brazil and its many realities. Courts and state-centrism; Administrative agencies and international cooperation.- Theoretical Perspectives of Constitutionalism, Globalism and Pluralism: Shades of Constitutions and Constitutionalism as a 3-Dimensional Concept. Cypriot Report for IACL Congress 2018.- "Friendliness" towards Others: How the German Constitution Deals with Legal Pluralism.- Between Constitutionalism and Legal Pluralism: Perspectives from Greece.- Constitutionalism: A bridge between the national and international law. The case of Russia.- Legal Centralism and Constitutional Minimalism in Singapore.- Constitutionalism and customary laws in Solomon Islands.- Report on Taiwan.- Accommodating legal pluralism and "pluralizing" the constitution: The example of the United Kingdom.

Guillaume Tusseau (Institut d'études politiques, Toulouse, 1997; Maîtrise de droit public, Toulouse, 1998; DEA de Théorie générale et philosophie du droit, Paris X - Nanterre, 1999; Docteur en droit public, Paris X - Nanterre, 2004) is professor of public law at Sciences Po Law School and member of the Institut universitaire de France. From 2015 to 2019, he has been a member of the High Council of the judiciary. His research interests include comparative law, constitutional law, and legal theory, fields in which he has extensively published and taught, in France and abroad.