This conference, organised by the MPI Luxembourg for Procedural Law and the University of Luxembourg, will seek to promote engagement with Pesctore's work, in particular with his construction of the Law of Integration. Pierre Pescatore was central to the elaboration of the doctrine at the service of a ‘constitutional vision of the legal order born of the Rome Treaties’ (Vauchez). This doctrinal idea has been at the heart of EU constitutional law. This conference will seek to shed light on the role of this doctrine on the evolution of EU law and conceptions of the European integrative project.