chief of staff

Chief of staff (or head of staff) is a leadership title with different meanings in civilian and military organizations. In civilian government organizations and businesses, a chief of staff is a primary aide-de-camp to an important individual, such as a president or leader of a large organization. In military organizations, a chief of staff is the leader of a complex organization, such as one of a country's armed forces, while the role that coordinates supporting staff for a senior military officer may be titled a principal staff officer (PSO).