Book excerpt: An excellent new analysis of federalism and the EU that investigates their mutual impact. It shows how scholars of comparative politics increasingly include the EU among their cases when investigating the impact of federalism on key issues such as policy making. The last decade saw a new wave of scholarly publications hit the shores as research on federalism and on the EU came together. These emerging strands of research genuinely enrich our understanding of the EU and its politics. Despite this recent wave, the topic of federalism and the EU is still extremely fruitful. This volume contributes to the continuing debate at a moment in time when the EU is undergoing profound changes. It is structured around four interrelated dimensions: the constitutional/theoretical dimension the institutional vision the party/citizens dimension the policy dimension. This structure allows the reader to consecutively "funnel down" from the more theoretical and abstract levels to the more concrete policy oriented level.