BackgroundBringing together professionals with different knowledge and skills comes with the opportunity to spur the innovativeness of primary care teams. Nevertheless, empirical evidence shows that it is not self-evident that these innovations are also realized. The social categorization theory suggests that a better understanding of whether these potential team innovations are realized can be obtained by looking at the social cohesion of such teams.PurposeThe aim of this study was to study the relationship between functional diversity and team innovation in primary care teams by examining the mediating role of social cohesion.MethodologySurvey responses and administrative data of 887 primary care professionals and 75 supervisors in 100 primary care teams were analyzed. Structural equation modeling was used to examine a curvilinear mediated relationship among functional diversity and team innovation through social cohesion.ResultsThe findings show a positive relationship between social cohesion and team innovation as expected. Contrary to the expectations, the relationship between functional diversity and social cohesion is insignificant, and the results show an inverted U-shaped relationship between functional diversity and team innovation instead.ConclusionsThis study reveals an unexpected inverted U-shaped relationship between functional diversity and team innovation. This relationship is not mediated by social cohesion; however, social cohesion is still a significant predictor of team innovation.Practice ImplicationsPolicymakers should be aware of the relevance as well as the complexity of creating social cohesion in functionally diverse primary care teams. As long as it remains unknown how social cohesion is stimulated in functionally diverse teams, it seems best for the team innovation to prevent bringing together too many, but also too few, different functions.