Over the past several decades the ‘affective revolution’ in cognitive psychology has emphasized the critical role affect and emotion play in human decision-making. Drawing on this affective literature, various commentators have recently proposed strategies for managing therapeutic expectation that use contextual, symbolic, or emotive interventions in the consent process to convey information or enhance comprehension. In this paper, we examine whether affective consent interventions that target affect and emotion can be reconciled with widely accepted standards for autonomous action. More specifically, the ethics of affective consent interventions is assessed in terms of key elements of autonomy, comprehension and voluntariness. While there may appear to be a moral obligation to manage the affective environment to ensure valid informed consent, in circumstances where volunteers may be prone to problematic therapeutic expectancy, this moral obligation needs to be weighed against the potential risks of human instrumentalization. At this point in time we do not have enough information to be able to justify clearly the programmatic manipulation of human subjects' affective states. The lack of knowledge about affective interventions requires corresponding caution in its ethical justification.