On the occasion of the 60th anniversary of the Universal Declaration of Human Rights, the objective of this research paper is to reflect on the impact that the appearance and development of International Human Rights Law has had on the functioning of different national law systems, specifically in Latin America, and to identify some of the interesting and demanding challenges, both theoretical and practical, that this phenomenon poses to the world of law. In the analysis of these transformations, some of the questions addressed are: the juridical grounding of the former; the complex task of how to harmonize, both political and legally, the national and international instances; some practical and operative problems that have appeared with the rise of the international courts that specialise in these issues. [ABSTRACT FROM AUTHOR]