The term dehumanisation refers to the ways in which a person is perceived to be less than human or treated as if they are less than human. It involves treating a person as if they are a child or infant, like an animal or non-living object, or as if they are dead, or any other way in which someone fails to be treated like a human being with an adult identity. Dehumanisation is widespread in dementia care; it is a major obstacle to person-centred care and has poor outcomes for people with dementia. This article proposes a new model of dehumanisation. The New Model presents a new way of describing dehumanisation that has been synthesised from current understanding about the phenomenon and reflects what is presently known about the subject. The model aims to summarise existing theories and models of dehumanisation and make dehumanisation theory accessible to students and trainees in healthcare. This article describes the new model, discusses existing models and theories in the literature, and explores the potential role of the new model in solutions for reducing dehumanisation in dementia care.