4-21. A warfighting function is a group of tasks and systems united by a common purpose that commanders use to accomplish missions and training objectives (ADP 3-0). The Army’s warfighting functions are fundamentally linked to the joint functions. A number of subordinate tasks, missions, and related capabilities help define each function; some apply to more than one function. The warfighting functions are the physical means that tactical commanders use to execute operations and accomplish missions assigned by superior tactical- and operational-level commanders. The purpose of warfighting functions is to provide an intellectual organization for common critical capabilities available to commanders and staffs at all echelons and levels of war. Commanders integrate and synchronize capabilities of one warfighting function with other warfighting functions to achieve objectives and accomplish missions. These grouped and related capabilities and activities help commanders and staffs integrate, synchronize, and direct operations. Commanders and staffs use the warfighting functions to ensure major groupings are accounted for in every operation and to conceptualize and apply capabilities to accomplish the mission through synchronizing forces and warfighting functions in time, space, and purpose. Combined arms operations use the capabilities of each warfighting function, along with leadership and information, in complementary and reinforcing capabilities.