Most jobs require teamwork. Are some people good team players? In this paper, we design and test a new method for identifying individual contributions to team production. We randomly assign people to multiple teams and predict team performance based on previously assessed individual skills. Some people consistently cause their team to exceed its predicted performance. We call these individuals “team players.” Team players score significantly higher on a well‐established measure of social intelligence, but do not differ across a variety of other dimensions, including IQ, personality, education, and gender. Social skills —defined as a single latent factor that combines social intelligence scores with the team player effect—improve team performance about as much as IQ. We find suggestive evidence that team players increase effort among teammates.

We introduce and validate a novel approach to identifying good managers. In a preregistered lab experiment, we causally identify managerial contributions by randomly assigning managers to teams and controlling for individual skill. We find that manager contributions are crucial for team success, and that people who self-select into management roles perform worse than randomly assigned managers. Managerial performance is strongly predicted by economic decision-making skill but not by demographic characteristics. Two validation studies support our experimental results. Participants who succeed in the lab receive more real-world promotions and, in a separate study of retail store managers, skill measures strongly predict store sales. A one standard deviation increase in manager quality increases annual per store sales by US$4.1 million (25% increase). Selecting managers on skills rather than demographic characteristics or the desire to lead could substantially improve organizational performance.