This article examines the notion of personhood and shows how it offers a robust conceptual underpinning to person-centred care. We use a fictitious case vignette to clarify the nature of personhood. Mental health professionals need a broad view of personhood, which we feel is best captured by regarding the person as a 'situated embodied agent'. Using this characterisation, we aim to demonstrate how it can underpin the notion of person-centred care and show the practical implications of this in connection with our fictitious case. The broad view supports a specific approach to people with dementia, but also shows the challenges that face the implementation of good-quality dementia care. Discussion of this case shows both the relevance of philosophy to clinical practice and the ways in which clinical practice can enrich the debates of philosophy.