Comparative constitutionalism has always been an important field of study. It has gained new importance, and practical urgency with the advent of emerging democratic governments. As part of the study of comparative constitutionalism, federal constitutional systems have also taken on a renewed interest at the beginning of the 21st century. Russia and South Africa present fascinating examples of emerging federal systems in which sub-national constitutions are beginning to play an important role. Within the field of comparative federal constitutional law, though, the study of state or subnational constitutions is only just becoming a major focal point of world-wide interest. Sub-national constitutions have been, and generally remain, low-visibility constitutions. Studies of constitutional federalism have tended to be almost exclusively top-down looks at the national constitution and its federal features rather than a bottom-up look at the national constituions themselves. A system of constitutional federalism cannot be fully understood without analyzing the constitutional arrangements within the constituent units. The marketplace for the constitutional ideas generated in the laboratories of states within the federal systems is rapidly expanding worldwide. There are several dozen bona fide federal political systems in the world, as well as unitary political systems that include federal arrangements. There is a range of general questions to be asked about the constitutions of states within any federal system. The contributions to this volume, in addition to their intrinsic interest, should serve as a database for answering those questions and describing the extraordinary diversity within and among subnational constitutions in federal systems. Moreover, each of the contributions include the texts of a number of representative sub-national constitutions.