In this paper we offer an argument against supererogation and in favour of moral perfectionism. We argue three primary points: 1) That the putative moral category is not generated by any of the main normative ethical systems, and it is difficult to find space for it in these systems at all; 2) That the primary support for supererogation is based on intuitions, which can be undercut by various other pieces of evidence; and 3) That there are better reasons to favour (...) perfectionism, including competing intuitions about the good-ought tie-up, and the epistemic preference for theoretical simplicity. (shrink)