The increasing prevalence of team-based organizations places a premium on leadership that will “mind the gap” and enable smooth synchronization of activities across multiple distinct teams. Prior work shows that leaders can be trained to directly facilitate between-team coordination processes. Yet relatively little is known about the intervening psychological mechanisms that enable between-team coordination. Here we advance multiteam-interaction mental models—cognitive structures containing knowledge of appropriate between-team activities—as one mechanism that facilitates coordination among multiple teams. We use leader and team cognition data gathered in DeChurch and Marks' (2006) MTS study to test these ideas. Results reveal leaders' multiteam-interaction mental model accuracy “transfers” to teams through strategic communication and leader strategic communication enables between-team coordination by promoting accuracy in followers' mental models. This study highlights the importance of leadership for developing collective cognition that allows teams to “scale up” from small stand-alone teams to larger and more complex systems.