On June 10, 2011, an important constitutional reform decree was published in Mexico that transformed the centuries-old categorization of fundamental rights and their protection and tutelage mechanisms as individual guarantees, to consider them henceforth as human rights. The decree instituted a clear system of recognition and control of international human rights conventions and incorporated the pro homine or pro personae principle to make it clear that the law must always be interpreted and applied in the manner that most favors the individual. This laid the foundations for the construction of a new legal system -which has been developing little by little through case law- centered on the human being as the main subject of the national legal order seen from an international perspective.