Background The acute hospital setting has become a key site of care for people living with dementia. The Department of Health and Social Care recognises that as many as one in four acute hospital beds in the UK will be occupied by a person living with dementia at any given time. However, people living with dementia are a highly vulnerable group within the hospital setting. Following an acute admission, their functional abilities can deteriorate quickly and significantly. Detailed research is required to understand the role and needs of health-care staff caring for this patient population and to explore what constitutes ‘good care’ for people living with dementia within the acute setting. Objectives The focus of this study was a common but poorly understood phenomenon within the acute setting: refusal and resistance to care. Our research questions were ‘How do ward staff respond to resistance to everyday care by people living with dementia being cared for on acute hospital wards?’ and ‘What is the perspective of patients and their carers?’. Design This ethnography was informed by the symbolic interactionist research tradition, focusing on understanding how action and meaning are constructed within a setting. In-depth evidence-based analysis of everyday care enabled us to understand how ward staff responded to the care needs of people living with dementia and to follow the consequences of their actions. Setting This ethnography was carried out on 155 days (over 18 months) in 10 wards within five hospitals across England and Wales, which were purposefully selected to represent a range of hospital types, geographies and socioeconomic catchments. Participants In addition to general observations, 155 participants took part directly in this study, contributing to 436 ethnographic interviews. Ten detailed case studies were also undertaken with people living with dementia. Results We identified high levels of resistance to care among people living with dementia within acute hospital wards. Every person living with dementia observed within an acute hospital ward resisted care at some point during their admission. Limitations Limitations identified included the potential for the Hawthorne or researcher effect to influence data collection and establishing the generalisability of findings. Conclusions Ward staff typically interpreted resistance as a feature of a dementia diagnosis, which overshadowed the person. However, resistance to care was typically a response to ward organisation and delivery of care and was typically rational to that person’s present ontology and perceptions. In response, nurses and health-care assistants used multiple interactional approaches that combined highly repetitive language with a focus on completing essential care on the body, which itself had a focus on the containment and restraint of the person in their bed or at their bedside. These approaches to patient care were a response to resistance but also a trigger for resistance, creating cycles of stress for patients, families and ward staff. The findings have informed the development of simple, no-cost innovations at the interactional and organisational level. A further study is examining continence care for people living with dementia in acute hospital settings. Funding The National Institute for Health Research Health Services and Delivery Research programme.