Although participatory approaches in health research are increasingly used, critical voices are being raised around lack of diversity among the public contributors involved. This article explores enabling and hindering factors in participatory meetings with forced migrants involved as public contributors in health research, using a convergent parallel mixed methods design including behavioural observations and questionnaires, with the aim of contributing to practices of meaningful and inclusive involvement in research. Our findings indicated that relationship-building and adapting to team development over time were key. Additionally, researcher responsivity and transparency enabled relevant contributions, but few decisions were taken. Although linguistic barriers existed and were rated higher by the researchers, engaging interpreters as co-facilitators of the meetings enabled nuanced discussions. In addition to following PPI recommendations, involving public contributors with experience of forced migration requires considering relationship-focused factors; inclusive communication, relationships and trust, and process-focused factors: where and how decisions are taken.