"Measuring and managing for team performance: Emerging principles from complex environments" Teamwork has always been an important component of successful military operations. However, as the nature of military operations evolves in the post-cold war era, the ability of teams to work effectively in a dynamic and complex environment may play an even more critical role. As the nature of military organizations evolves and becomes more complex, it will be important to understand why some teams function better than others and how to instill the requisite skills in numerous geographically dispersed teams. The authors of this paper extracted twenty principles of teamwork from studies of decision making teams working in three complex tactical naval settings. Nine of the principles regard the nature of teamwork; seven regard team leadership; four regard the roles of individual team members. The findings presented here provide suggestions for managing teams effectively, measuring team performance, and for training teams in complex settings. They have application to peacekeeping operations, which are highly complex.