There is a growing recognition that needs more to be done to ensure that research contributes to better health services and patient outcomes. Stakeholder engagement in research, including co-production, has been identified as a promising mechanism for improving the value, relevance and utilization of research. This article presents findings from a prospective study which explored the impact of stakeholder engagement in a 3-year European tobacco control research project. That research project aimed to engage stakeholders in the development, testing and dissemination of a return-on-investment tool across five EU countries (the Netherlands, Spain, Hungary, Germany and the UK). The prospective study comprised interviews, observations and document review. The analysis focused on the extent to which the project team recognized, conceptualized and operationalized stakeholder engagement over the course of the research project. Stakeholder engagement in the European research project was conceptualized as a key feature of pre-designated spaces within their work programme. Over the course of the project, however, the tool development work and stakeholder engagement activities decoupled. While the modelling and tool development became more secluded, stakeholder engagement activities subtly transformed from co-production, to consultation, to something more recognizable as research participation. The contribution of this article is not to argue against the potential contribution of stakeholder engagement and co-production, but to show how even well-planned engagement activities can be diverted within the existing research funding and research production systems where non-research stakeholders remain at the margins and can even be seen as a threat to academic identify and autonomy.