This case study is based on a co-operative inquiry project titled ‘The Changing Face of our Neighborhoods’, which is a suite of three cultural heritage films co-produced alongside the Open Doors Research Group in Salford, Greater Manchester, UK (see: https://salfordneighbourhoods.wordpress.com/films/). The Open Doors Research Group operated as a sub-group of the Open Doors Dementia Service which is a peer support group for people living with dementia and their care partners and has been supported by Greater Manchester Mental Health NHS Foundation Trust over the last decade. Co-operative inquiry is part of the participatory research paradigm and is an under-reported and novel approach in the field of dementia research. We worked alongside people living with dementia (with and without capacity) as co-researchers in a collaborative and shared decision-making enterprise. Implementing co-operative inquiry alongside people living with dementia presented a number of challenges for co-researchers and academic researchers alike, and in this case we will share our reflections on some of the main ethical dimensions and shared decision-making processes that were faced over the continuum of the study.