Abstract Background Interest in and use of co-production in healthcare services and research is growing. Previous reviews have summarized co-production approaches in use, collated outcomes and effects of co-production, and focused on replicability and reporting, but none have critically reflected on how co-production in applied health research might be evolving and the implications of this for future research. We conducted this scoping review to systematically map recent literature on co-production in applied health research in the United Kingdom to inform co-production practice and guide future methodological research. Methods This scoping review was performed using established methods. We created an evidence map to show the extent and nature of the literature on co-production and applied health research, based on which we described the characteristics of the articles and scope of the literature and summarized conceptualizations of co-production and how it was implemented. We extracted implications for co-production practice or future research and conducted a content analysis of this information to identify lessons for the practice of co-production and themes for future methodological research. Results Nineteen articles reporting co-produced complex interventions and 64 reporting co-production in applied health research met the inclusion criteria. Lessons for the practice of co-production and requirements for co-production to become more embedded in organizational structures included (1) the capacity to implement co-produced interventions, (2) the skill set needed for co-production, (3) multiple levels of engagement and negotiation, and (4) funding and institutional arrangements for meaningful co-production. Themes for future research on co-production included (1) who to involve in co-production and how, (2) evaluating outcomes of co-production, (3) the language and practice of co-production, (4) documenting costs and challenges, and (5) vital components or best practice for co-production. Conclusion Researchers are operationalizing co-production in various ways, often without the necessary financial and organizational support required and the right conditions for success. We argue for accepting the diversity in approaches to co-production, call on researchers to be clearer in their reporting of these approaches, and make suggestions for what researchers should record. To support co-production of research, changes to entrenched academic and scientific practices are needed. Protocol registration details: The protocol for the scoping review was registered with protocols.io on 19 October 2021: https://dx.doi.org/10.17504/protocols.io.by7epzje
