1-19. Teams are an essential configuration of how people come together to accomplish missions. In the Army, teams occur throughout every structure level of the organization. The Army as a whole is teams of teams. It begins with buddy teams––two military members who look after each other in a variety of positions and environments. The missions of the Army demand that leaders and teams be developed and ready. It is proven that a team is more effective than an individual when members work together, using their unique skills, experiences, and capabilities. The Army leadership competency categories cover how Army leaders lead; develop themselves, their subordinates, and organizations; and bring efforts together to achieve results. Army leaders are charged with developing others and conducting team building. Holistic leader development programs contribute to unit cohesion, resilience, and agility by producing leaders and teams that are creative, life-long learners, adaptable, and capable of exercising mission command.