Introduction Dementia and Imagination is a multi-disciplinary research collaboration bringing together arts and science to address current evidence limitations around the benefits of visual art activities in dementia care. The research questions ask; can art improve quality of life and well-being? If it does make a difference, how does it do this - and why? Does it have wider social and community benefits? Methods and analysis This mixed-methods study recruits participants from residential care homes, NHS wards and communities in England and Wales. A visual art intervention is developed and delivered as 1 x 2 hour weekly group session for 3 months in care and community settings to N=100 people living with dementia. Quantitative and qualitative data are collected at three time-points to examine the impact on their quality of life, and the perceptions of those who care for them (N=100 family and professional carers). Repeated-measures systematic observations of well-being are obtained during the intervention (intervention versus control condition). The health economics component conducts a social return on investment evaluation of the intervention. Qualitative data is collected at three time-points (n=35 carers/staff and n=35 people living with dementia) to explore changes in social connectedness. Self-reported outcomes of the intervention delivery are obtained (n=100). Focus groups with intervention participants (n=40) explore perceptions of impact. Social network analysis of quantitative and qualitative data from arts and healthcare professionals (N=100) examine changes in perceptions and practice. Ethics and dissemination The study is approved by North Wales research ethics committee – West. A range of activities will share the research findings, including international and national academic conferences, quarterly newsletters and the project website. Public engagement projects will target a broad range of stakeholders. Policy and practice summaries will be developed. The visual art intervention protocol will be developed as a freely available practitioners guide.