This book explores how regional political parties use Europe to advance their territorial projects in times of rapid state restructuring. It examines the ways in which decentralization and supranational integration have encouraged regional parties to pursue their strategies across multiple territorial levels. This book constitutes the first attempt to unravel the complexities of how nationalist and statewide parties manoeuvre around the twin issues of European integration and decentralization, and exploit the shifting linkages within multi-level political systems. In a detailed comparative examination of three cases - Scotland, Bavaria and Sardinia - over a thirty-year period, the book explores how integration has altered the nature of territorial party competition and identifies the limits of Europe for territorial projects. In addressing these issues, this work moves beyond present scholarship on multi-level governance to explain the diversity of regional responses to Europe. By providing important new insights and empirical research on the conduct of territorial party politics, and an innovative model of territorial mobilization in Europe, this book will be of great interest to students and scholars of comparative politics, European studies, regionalism and federalism, political parties and devolution.