By assigning people to multiple teams at once, organizations can make more-efficient use of time and brainpower and do a better job of solving complex problems and sharing knowledge across groups. But competing priorities and other conflicts can make it hard for teams with overlapping membership to stay on track. Group cohesion often suffers, and people serving on several teams concurrently may experience burnout. Through extensive research and consulting, the authors have identified several ways that both team and organizational leaders can reduce the costs of multiteaming and better capitalize on its advantages. Team leaders should launch the team well to establish trust and familiarity, map every member's skills, carefully manage time across teams, and boost motivation by emphasizing opportunities to learn. Organizational leaders should focus on mapping and analyzing patterns of team overlap, promoting knowledge flows among teams, and buffering teams against shocks. All this represents a significant investment of time and effort. But organizations pay a much higher price when they neglect the costs of multiteaming in hot pursuit of its benefits.

Over the years, as teams have grown more diverse, dispersed, digital, and dynamic, collaboration has become more complex. But though teams face new challenges, their success still depends on a core set of fundamentals. As J. Richard Hackman, who began researching teams in the 1970s, discovered, what matters most isn't the personalities or behavior of the team members; it's whether a team has a compelling direction, a strong structure, and a supportive context. In their own research, Haas and Mortensen have found that teams need those three "enabling conditions" now more than ever. But their work also revealed that today's teams are especially prone to two corrosive problems: "us versus them" thinking and incomplete information. Overcoming those pitfalls requires a new enabling condition: a shared mindset. This article details what team leaders should do to establish the four foundations for success. For instance, to promote a shared mindset, leaders should foster a common identity and common understanding among team members, with techniques such as "structured unstructured time." The authors also describe how to evaluate a team's effectiveness, providing an assessment leaders can take to see what's working and where there's room for improvement.