The Joint Chiefs of Staff consists of senior officers from the military services, who advise the Secretary of Defense, the Homeland Security Council, the National Security Council and the President of the United States on military matters. In addition to the Chairman and Vice Chairman, the other members are the chiefs of the Army, Navy, Air Force, Marine Corps and the National Guard Bureau.
The Goldwater-Nichols Act of 1986 specified that the Joint Chiefs of Staff do not have operational command authority, and that the chain of command goes from the President to the Secretary of Defense, and from there to the commanders of the combatant commands.
The current JCS is a successor to the Joint Army and Navy Board, established by Theodore Roosevelt in 1903 to foster cooperation between the services. It was initially of little importance. The need for better coordination became apparent with the onset of World War II, and the first meeting of the reorganized and renamed Joint Chiefs of Staff took place in 1942.