Multilateralism seems to deserve a reflection because it is nowadays and has been for a while called into question. The idea of multilateralism, devised during the last third of the nineteenth century and having made amazing progress during the twentieth, is now being questioned. Could it be outdated? The question might look audacious, if not excessive. Multilateralism is obviously not threatening to disappear and each day gives indeed evidence that it is very much alive. Nevertheless, it cannot escape questions that seem related to the debate on fragmentation, which has unfolded in international law over the course of the past two decades.

This lecture will focus in particular on the question of legitimacy, through an exploration of the role of multilateralism at the World Trade Organisation.