Psychiatric patients may try (or express a desire) to injure themselves in hospital in order to cope with overwhelming emotional pain. Some health care practitioners and patients propose allowing a controlled amount of self-injury to occur in inpatient facilities, so as to prevent escalation of distress. Is this approach an example of professional assistance with harm? Or, is the approach more likely to minimise harm, by ensuring safer self-injury? In this article, I argue that health care practitioners who use harm-minimisation (...) can be considered to be helping physical injury to occur, although they do not encourage the act. I consider why there are compelling reasons to believe that a patient who self-injures is not maximally autonomous in relation to that choice. However, I then move onto argue that allowing a degree of self-injury may enable engagement with psychotherapy (enhancing autonomy) and behavioural change. In these circumstances, allowing injury (with precautions) may not be harm, all things considered. (shrink)