Treballs finals del Màster "Estudios Internacionales: organizaciones internacionales y cooperación – Colección Memorias MEI", Facultat de Dret, Universitat de Barcelona, Curs:2015-2016, Tutora: Milagros Álvarez VerdugoDuring the last decades, the meaning of sovereignty has been expanded, and nowadays it is perceived not only as a right of states but also as a responsibility towards their people. In this spirit, a doctrine of human protection was born, the Responsibility to Protect, with the aim of responding to mass atrocities. However, the political nature of the Security Council and the veto power of its permanent members can hinder the application of the doctrine. The objective of this thesis is to spell out the dysfunctional dynamics between the veto and the doctrine and explore in what way the Security Council decisions could be subjected to a set of principles in R2P cases. The recent examples of Libya and Syria will be used to manifest how two very similar cases can been dealt with diametrically differently due to the veto use.