In this paper, I focus on a kind of medical intervention that is at the same time fascinating and disturbing: identity-changing interventions. My guiding question is how such interventions can be ethically justified within the bounds of contemporary bioethical mainstream that places great weight on the patient's informed consent. The answer that is standardly given today is that patients should be informed about the identity effects, thus suggesting that changes in identity can be treated like ‘normal’ side effects. In the paper, I argue that this approach is seriously lacking because it misses important complexities going along with decisions involving identity changes and consequently runs into mistakes. As a remedy I propose a new approach, the ‘perspective-sensitive account’, which avoids these mistakes and thus provides the conceptual resources to systematically reflect on and give a valid consent to identity-changing interventions.