The book aims to research the conception and development of the Responsibility to Protect (R2P) as a norm of international law that calls on the international community to act, either by assisting states in a preventive manner, according to pillar II, or by acting through the responsibility to react in favor of human protection, according to pillar III, through the means provided for in the UN Charter and other rules of international law, including the International Law of Refuge. In the case of the Syrian civil war, due to the Security Council's failure to fulfill its mandate, alternative measures must be explored under pillar III of R2P. Since R2P was drafted with a focus on the protection of human beings in order to prevent and/or alleviate suffering and promote assistance for humanitarian purposes in the face of mass atrocities, it is of the utmost importance to analyze legitimate alternatives that can serve as measures to implement R2P in such a way that they are not restricted to the endorsement of the Security Council or limited to military actions.