The process of fragmentation of the international legal order and the absence of constitutional devices governing the connections between the various legal regimes can be reduced to a rational picture only through the activity of the judges.Against this background, the judges play a crucial role in creating connections between legal regimes and proceedings.The metaphor of dialogue has been vastly used by the literature and this concept was variously understood in different meanings: vehicle for transplants, informal way of communication between judicial and political bodies, new paradigm of judicial relations between actors not belonging to the same legal order.Starting from this assumption we attempted to put together scholars belonging to different fields of research (Constitutional Law, EU Law, WTO Law, Public International Law, Jurisprudence) in order to carry out a comprehensive appraisal of this phenomenon, and to provide a wide picture of the latest development of the role of the judges in the international legal order.Paolo Carrozza is Full Professor of Comparative Constitutional Law at the Scuola Superiore Sant'Anna and at the University of Pisa. Giuseppe Martinico obtained a PhD in "Individual Person and legal protection" (curriculum EU Constitutional law)" from the Sant'Anna School of Advanced Studies, Pisa, Italy, where he is also conducting his post-doctoral research.Filippo Fontanelli is completing a PhD in "Individual person and legal protection" at the Sant'Anna School of Advanced Studies, Pisa, Italy, and he is currently LL.M. Global Hauser Scholar at the New York University Law School.