The responsibility to protect (R2P) and the question of UN Security Council veto constraint are intimately linked, but whilst the R2P has become increasingly embedded in diplomatic discourse and practice, the idea that in relation to it the Council’s five permanent members should recognize a ‘responsibility not to veto’ (RN2V) has fared less well. This chapter examines why this should be so. In its assessment of the prospects for, and pros and cons of, veto-restriction, the chapter argues that opposition amongst the P5 to the idea of a RN2V is unlikely to change in the foreseeable future, and it charges advocates of the idea with a failure to recognize that it is ill-conceived to believe that R2P can transcend great power cleavages in international society, whether these stem from principles of prudence, conflicting value systems, or the play of self-interest and great power jockeying for position.