Possession states are a complex phenomenon that takes a variety of different cultural and religious forms, which may or may not be associated with a psychiatric diagnosis. A case study demonstrates how demonic attributions may be employed as a form of negative religious coping and may lead to spiritual struggles. It illustrates the importance of understanding theological/religious context of belief in spirit possession and the difficulties of reaching a psychiatric diagnosis when the patient belongs to a faith community that understands such experiences as spiritually determined and not symptomatic of illness. Possession states are considered unusual in the UK and yet they are very common worldwide. Exorcism (or disobsession or spirit release) has in some contexts been proposed as an appropriate (if controversial) psychiatric treatment. While, in appropriate religious/cultural contexts, it can be helpful, there is also evidence that it can be harmful when applied in the wrong way to patients with certain diagnoses. This raises important questions about collaboration with faith leaders, safeguarding those who are vulnerable and not pathologising culturally normative practices.