This is an account of the development of European labour and social security law as it interrelates with the evolution of market integration in the European Union. Giubboni presents, from a labour law perspective, a case study of the changes the European Community/European Union has undergone from its origins to the present day and of the ways these changes have affected the regulation of European Welfare States at national level. Drawing on the idea of ‘embedded liberalism’, Giubboni analyses the infiltration of EC competition and market law into national systems of labour and social security law and provides a normative framework for conceptualising the transformation of regulatory techniques implemented at the EU level. This important, interdisciplinary contribution to research in EU social law illustrates how the vision of social protection and solidarity is changing.