Throughout the world, liberal-democracies are grappling with increasing claims made in the name of minority national, socio-cultural and ethno-cultural identities that seek greater recognition in the institutions of the nation-state. This work inserts itself into debates centred on diversity through a normative and empirical analytical assessment of the political sociology of multinational democracies. The main thread of the arguments put forward is that federalism, in both its institutional manifestations and its sociological properties, constitutes a promising avenue for the management of cohabitating political communities and for the affirmation of collective identities within states that are constituted by two or more nations. Author Alain-G Gagnon develops his argument by contending that the federal principle allows for the exercise of advanced democratic practices within nation-states, permitting internal nations to openly affirm the bases of adherence to a common political project. At the same time, he argues that federalism nourishes the development of distinct collective traditions that serve to benefit all parties to the association. It is concluded that only in such a scenario will the elusive pursuit of an authentic and shared loyalty underpin multination states and ensure their stability, in contrast to the instrumental sentiments of belonging engendered by procedural territorial federal models. Focusing primarily on the Canadian case, this book also draws inspiration from other federal states (Belgium, the United States), as well as federalizing states (Spain, the United Kingdom). It will be of keen interest to students and scholars of Politics, European Studies, along with Nationalism and Federalism Studies.