Jean-Claude Piris is President of Piris Consuting (European and Public International Law), a retired French Conseiller d'Etat, a former diplomat to the UN and former Director of Legal Affairs at the OECD, and was Director General of the Legal Service of the Council of the European Union for over 20 years. He has written several books with Cambridge University Press, most recently The Future of Europe: Towards a Two-Speed EU? (2012).