Conference organized at la Maison du Barreau (Paris) on March 16, 2007 by the Association of the Councils of State and the supreme administrative Jurisdictions of the EU, the French Conseil d'Etat, the Mission of research "Law and Justice", and the Faculty of Law of Limoges, the University Paris-1 - Pantheon-Sorbonne, with the support of TAIEX, European Commission.