On February 14, 1967, the Treaty of Tlatelolco was signed, the name by which the Treaty on the Prohibition of Nuclear Weapons in Latin America is commonly known. The Mexican initiative embodied in this legal instrument shows the importance of imagination, political will and active diplomatic coordination to stimulate the transformation of the different international scenarios into a safe and stable planetary home. This is the central theme of this issue of the Revista Mexicana de Política Exterior. The “Essays” section contains the exhibitions that were held in February 1987 to commemorate the 20th anniversary of the Treaty. The “Notes and Reports” section reproduces the Rapporteurship and the Declaration of Mexico, issued at the end of the extraordinary conference of ECLAC that took place in the capital of the Republic. In the “Speeches and documents” section, some of the most relevant communiqués issued by the Contadora Group and other texts referring to Mexico's bilateral relations are grouped. In commemorating the 20th anniversary of the Treaty of Tlatelolco, the Revista Mexicana de Política Exterior expresses its hope that continental thinking and political coordination in Latin America yield their best results for the benefit of our peoples.