This paper defends the doctrine that moral requirements are categorical in nature. My point of departure is John McDowell’s 1978 essay, “Are Moral Requirements Hypothetical Imperatives?”, in which McDowell argues, against Philippa Foot, that moral reasons are not conditional upon agents’ desires and are, in a certain sense, inescapable. After expounding McDowell’s view, exploring his idea that moral requirements “silence” other considerations and discussing its particularist ethos, I address an objection that moral reasons, as McDowell conceives them, are fundamentally incomplete (...) in ways only a full-bloodedly Kantian appeal to pure practical reason can remedy. I conclude that the objection fails: ordinary moral reasons do not stand in need of a grounding in Reason. There is no prospect of deriving them from a supreme principle of morality or other canons of rationality. Ordinary reasons are sufficient in themselves, though their significance can be elucidated and illuminated by various strategies — some broadly Aristotelian, some drawing inspiration from Kant’s formula of humanity — in ways that can strengthen and vindicate them. Notwithstanding the failure of the objection, I conclude by reflecting on how Kantian insights can yet play a significant role in a McDowellian view of moral deliberation and moral education. (shrink)