Abstract: This paper builds on the results obtained in the so-called Blurring Boundaries project which was undertaken at the Law Department, Copenhagen Business School, in the period from 2007 to 2009. It looks at the sustainability of the Danish welfare state in an EU law context and on the integration of welfare functions into EU law both from an internal market law and a constitutional law perspective. The main problem areas covered by the Blurring Boundaries project were studied in sub-projects on: 1) Internal market law and welfare services, 2) Fundamental rights and non-discrimination law aspects, and 3) Services of general interest. In the Blurring Boundaries project, three aspects of the European Social Model have been particularly highlighted:

• the constitutionalisation of the European Social Model,
• its multi-level legal character, and
• the clash between market access justice at EU level and distributive justice at national level.