The causes that led to this study are, mainly, the violation of human rights and its lack of protection both in Mexico and in Latin America. By not finding a solution in the internal headquarters, the victims and their defenders find hope in the Inter-American Commission on Human Rights. According to the above, the work is divided into four chapters: the first deals with conceptual references of Precautionary Measures from the classical theory, its object and purpose, characteristics, procedural budgets, its classification and legal nature, as well as the procedure for its adoption. The second chapter outlines conceptual referents, characteristics, procedural budgets and adoption procedure, rights and freedoms that protect, collective cases benefited from the aforementioned international protection mechanism, cases within the Inter-American Commission on Human Rights during the petition , classification of the Precautionary Measures, and their legal nature in relation to the principle of good faith. In the third chapter expresses the obligation of the State in particular: the control of conventionality. The jurisprudence of the CORTEIDH is reflected in connection with the principle of good faith and reflects on the useful effect of the inter-American treaties. Finally, it details the duty of the internal authorities regarding the compliance of the Mc, as well as the rights that they protect according to the jurisprudence of the Constitutional Court of Colombia. The fourth chapter analyzes the discretionary power of the IACHR to adopt Precautionary Measures, the lack of specific means to comply with its object and purpose within the State, the ductile nature of the Mc, the context on the human rights situation in Latin America and Mexico, as well as the general duty of the Mexican State, the barriers that prevent the effectiveness of the Precautionary Measures and the alternative.