In federal systems, the constitution protects all the issues that enable the federal structure to maintain a sustainable and lasting equilibrium between the centre and the periphery. These issues include the allocation of legislative powers, the structure of institutions, the autonomy of federated and federal entities, the settlement of disputes between them, and so on. Since these matters are enshrined in the constitution, amending its text is of fundamental importance in any federal system. Fdralisme compar et modification constitutionnelle offers a comparative study of the constitutional amendment procedure in ten federal systems, with the aim of contextualizing the Canadian process. This book examines the federal systems of Canada as well as Australia, Austria, Belgium, the European Union, Germany, Italy, Spain, Switzerland, and the United States. To systematically compare these ten processes, the book investigates constitutional amendment procedures at various stages, ultimately suggesting the creation of an index for better analysis and comparison.