All federal systems face an internal tension between divisive and integrative political forces, striking a balance between providing local autonomy and sub-national representation on one hand, and maintaining an integrated political community and sufficient integration to maintain stability on the other hand. This book argues that parties and voters strategically respond to the incentives of federal institutional design to shape the development of arenas of political competition that are either predominantly independent or integrated across levels of the federation. Drawing on a rich collection of original data, including a dataset of aggregate level electoral data from over 2200 federal and state-level elections in seven federations, as well as the author's original dataset on party organizational linkage from a survey of sub-national party elites, this book demonstrates how two aspects of institutional design — the degree of decentralization and the method of power allocation, affect the development of integrated or independent politics as observed through voter behaviour, party systems and party organization. Using a mixed method research design, it demonstrates how voters and parties react to federal institutional design. It also provides nuance in the causal processes at play, demonstrating how party organization, party system structure and voter behaviour interact, to produce a federalism that is predominantly integrating and stability-enhancing or one that is predominantly autonomy- and accountability-enhancing. Comparative Politics is a series for researchers, teachers, and students of political science that deals with contemporary government and politics. Global in scope, books in the series are characterised by a stress on comparative analysis and strong methodological rigour. The series is published in association with the European Consortium for Political Research. For more information visit: www.ecprnet.eu. The series is edited by Susan Scarrow, Chair of the Department of Political Science, University of Houston, and Jonathan Slapin, Professor of Political Institutions and European Politics, Department of Political Science, University of Zurich.