While global constitutional ideas migrate across countries, continents, agencies and institutions, internationally accepted principles of constitutionalism and human rights influence national governments that have been able to keep their sovereignty. This book looks into the fascinating question of convergence and sovereignty by approaching the issue from various angels: the use of foreign and international law in national constitution-making and constitutional interpretation on the one hand, and the use of international human rights by domestic courts on the other. The book covers ten countries through different perspectives, focussing on the interplay between the national jurisdiction and international and foreign law. The author argues that despite the different postures towards the use of foreign and international law, constitutionalism and judicial review have `gone global, and there is definitely a growing horizontal communication between constitutional systems. The consequence of this development is the emergence of a `transnational or cosmopolitan constitutionalism. According to the author, this process can be sped up by the inevitable constitutionalization of international law.