Abstract
In this paper, I pose a dilemma for a very influential kind of metaethical constructivism, advocated recently by Sharon Street. It is either true or false that, if an action is morally wrong for a certain agent, then that agent has a normative reason not to do it. If it is true, then the constructivist is committed to the counterintuitive claim that some apparently morally horrendous acts are not actually wrong. If it is false, then the constructivist cannot maintain a distinctively metaethical constructivism. Either way, this type of constructivism comes with a significant cost.