Community engagement in the research process is more than communication and outreach. It is a process of co-production of knowledge. The co-production of knowledge starts and ends at the “small” local level but is embedded in “big” processes that are nested in academic and research institution priorities. This chapter problematizes the issues of small-to-big science and reflects on limitations related to community engagement in research such as community research fatigue, un-standardized research ethics protocols across research institutions, and limitations in funding bodies' budget schemes. It considers lessons learned by theorizing a “sliding scale of community engagement” that can be used to conceptualize the definitions of community engagement activities within a large research project. The chapter also places emphasis on discussion of the community-engagement experiences of the Nordforsk-funded Nordic Center of Excellence project Arctic Climate Predictions: Pathways to Resilient, Sustainable Societies (ARCPATH). This project has facilitated excellent collaboration with our informants in our research communities and hence provides a significant example of the co-production of knowledge that we seek to encourage.