Reform of end of life care in England has been a priority for some time, with a desire, amongst other things, to ensure that more people can have a ‘good death’ in line with their wishes for what this would be and where this might happen. Advance care planning (ACP) is a key element in this end-of-life care in England. An economic perspective policy, with an important role for social care envisaged. The complex interventions that research suggests are most effective and the social care role within them are, however, under-developed. While research evidence suggests that ACP interventions are associated with improved quality outcomes and potential acute-care cost savings, interventions are poorly described in the literature, and information on costs and cost drivers is almost entirely lacking. This project addresses these gaps, identifying and interrogating the activities and resources needed to deliver complex ACP interventions, drawing on the experiences of ACP programmes in the US and Australia, including Respecting Choices and four programmes adapting this approach. These programmes use (or, in Australia, are considering use of) social workers, allied professionals and volunteers as facilitators. We will use quantitative and in-depth qualitative methods to produce detailed descriptions of the programmes and their practices, develop a method for costing them, collect and compare cost data, and explore the main cost drivers and sources of cost variation. We shall also review the literature to identify, and ideally model, the likely economic and quality outcomes of such interventions in England. We will work with an expert advisory panel and facilitate a stakeholder workshop to comprehensively consider transferability into an English context.