AbstractAs the prevalence of multiple team membership (MTM) arrangements continues to grow, researchers have argued that shifting between teams and work roles induces MTM identity strain and other harmful outcomes. Drawing from work role transitions research on role identity and integrating it with social identity theory, we investigate this line of reasoning by conducting two studies, one field and one online panel study, focusing on blended MTMs, in which employees are concurrently assigned to a permanent team and several temporary project teams. Specifically, we examine the theoretical mechanisms explaining a positive relationship between number of temporary teams and turnover decisions. In Study 1, we surprisingly found that number of temporary teams negatively related to turnover decisions through MTM identity strain with permanent team identification strengthening this effect. In contrast, in Study 2, we found support for the hypothesized relationships: number of teams indirectly positively related to turnover intentions, mediated by MTM identity strain and cognitive depletion, and permanent team identification weakened the indirect effect. We provide explanations for these mixed findings and suggest theoretical and practical implications for MTM research.