Published in the Psychological Science Agenda, the following brief identifies the five conditions that, when present, increase the probability of team effectiveness. Teams should have clear boundaries, a clear purpose, and interdependence among its members. Its social system context should provide resources and support that members need to carry out their collective work, and competent coaching should be available for all members. Furthermore, effective team leaders should be carefully selected and competently trained, but should also be willing to improvise.