The idea behind the works gathered in this special issue of the Revista Mexicana de Política Exterior is the need to identify the challenges that arise in the international legal field to adapt Mexico’s foreign policy to contemporary needs. Examining those challenges in depth would have required more time and space. This compilation only intends to draw attention to the subject, through some case studies. Specifically, the essays in this volume highlight the influence of three types of legal norms on current Mexican foreign policy: the internal laws of other countries that, in some way, affect Mexicans; the internal laws of extraterritorial vocation that, in addition to affecting them, violate international law; and the new multilateral rules that have influenced or will influence Mexico's foreign policy.