In a widely cited and controversial speech, UN Secretary-General Kofi Annan highlighted the moral character of the boundaries of political sovereignty when he questioned whether respecting national sovereignty everywhere and always precluded the international protection of human rights. He argued that it did not and highlighted the importance of multilateral authorization. In this article, I explore the difference that multilateral authority, as opposed to unilateral national decision, should make in justifying armed intervention. Should the more salient role of the United Nations lead us to a more expansive tolerance of international intervention? And, if multilateralism does make a difference—and many think its impartiality is key—are good intentions enough? Had the international community also discovered how to intervene more effectively, with a better prospect of self-sustaining self-determination, at an acceptable humanitarian cost? I will conclude that multilateralism should widen our acceptance of intervention, even though the intentions at play are not reliably superior to unilateral intentions.