Participatory action research (PAR) is a form of collaborative research particularly concerned with power inequities of marginalized communities. With this approach, occupational therapists can work with clients and communities to address issues of access, inclusion, equity and collaboration in practice and research. This paper begins with a summary of key concepts and controversies related to participatory action research. Two examples from occupational therapy experience are used to demonstrate the initial steps and key principles of PAR projects and to highlight the conceptual links between PAR and community-based, client-centred occupational therapy. One project involved a group of mental health consumers, the other a community group of older adults. Several challenges and potential outcomes in PAR projects are highlighted in this examination of the complexity of PAR processes. The paper concludes by identifying possibilities and obstacles to the further use of PAR in occupational therapy.