In the past decades the coordination of social security provisions of the European Union have become of vital importance. This book gives a clear overview of the main lines and main developments of this significant part of EU law.On 1 May 2010 a new Coordination Regulation on social security for migrant workers, Regulation 883/2004, came into force. Since then there has been important case law and there have been very interesting developments, in particular in the area of posting of workers and the influence of the Treaty on the interpretation of coordination provisions. Also the development of the concept of EU citizenship has had an important impact on access to social rights. This book gives a clear overview of these developments, their effects on national case law and the differences with the old coordination Regulation.A second main part of EU social security law is that of social policy. In this book the main developments of the equal treatment law of men and women are explained and in addition the present social policy measures and the instruments employed in this area are outlined.This book is the sixth edition of this authoritative handbook, which is used in many courses on European social security and of which already several translations have been made in other languages.