The aim of this book is to examine how EU law relates to and impacts the national social security systems of the member states. It asks three key questions: how have the internal market and its developments informed member states' social security regimes, despite the fact the the EU has limited competence in the field; how has Union citizenship and the Charter of Fundamental Rights affected the coordination of these regimes; and, finally, it asks whether the national structures of these regimes can affect the degree of the impact of EU law. Based on a revised Phd thesis. (Series: Modern...