This book presents the results of research project financed by the Hague Institute for the Internationalization of Law (HiiL) and carried out at the Tilburg Law and Economics Center (TILEC) of Tilburg University. The project team shows that globalization, instead of threatening national legal systems, put them in a new role and gives them continuing relevance. First of all, once one takes a more functional view of the law, based on law and economics and comparative law literature, harmonization or unification of national legal systems is no longer a foregone conclusion. Secondly, fundamental constitutional principles continue to bear in the era of multi-level and transnational governance: