This United States Chairman of the Joint Chiefs of Staff manual, Joint Publication JP 1-0 Joint Personnel Support December 2020, is the keystone document of the personnel series. It provides fundamental principles and guidance to plan, coordinate, provide, and assess manpower and personnel support to joint operations. JP 1-0 describes the principles of personnel support, organization, and function. It outlines the responsibilities of Secretary of Defense, Chairman of the Joint Chiefs of Staff, Military Department Secretaries, Service chiefs, Department of Defense Agencies, and combatant commanders in relation to personnel policies. This publication discusses joint force command manpower and personnel directorate and Service component responsibilities for manpower management, personnel management, and personnel support. It describes considerations for joint personnel planning and the means by which the manpower and personnel directorate of a joint staff envisions the desired objective(s) in support of the commander's mission requirements. Prepared under the direction of the Chairman of the Joint Chiefs of Staff (CJCS) JP 1-0 sets forth joint doctrine to govern the activities and performance of the Armed Forces of the United States in joint operations, and it provides considerations for military interaction with governmental and nongovernmental agencies, multinational forces, and other interorganizational partners. It provides military guidance for the exercise of authority by combatant commanders and other joint force commanders (JFCs), and prescribes joint doctrine for operations and training. It provides military guidance for use by the Armed Forces of the United States in preparing and executing their plans and orders. Joint doctrine established in this publication, JP 1-0, applies to the Joint Staff, combatant commands, subordinate unified commands, joint task forces, subordinate components of these commands, the Services, the National Guard Bureau, and combat support agencies.