Philosophers spend a lot of time discussing what consent is. In this chapter, Alexander Guerrero suggests that there are also hard and important epistemological questions about consent and that debates about consent often mistake epistemological issues for metaphysical ones. People who defend so-called “affirmative consent” views sometimes are accused of, or even take themselves to be, offering a new, controversial view about the nature of consent. Guerrero argues that this is a mistake. The right way of understanding “affirmative consent” is as a view about what is required, epistemically, before one can justifiably believe that another person has consented. This view will be justified, if it is, because of background views about epistemic justification and the way epistemic justification interacts with moral norms governing action. Guerrero concludes by discussing the implications of this view for the morality and law regarding consent.