Their lack of effectiveness was often condemned and the cases of their violations are numerous. Since this tool is the most compelling the United Nations can use to reduce a conflict – apart from the use of armed force itself – its failure to be respected poses the problem of the necessary improvement of its efficacy. The closely linked embargoes on Sierra Leone and Liberia provide an interesting study framework for possible reforms of the system. The implementation of these embargoes could be studied in depth and with detachment as these countries share a common border. Within this framework, we can analyze the weaknesses of the system, but also the means of improving it.