A Naval Staff is a organised group of the most senior military officers at a central command headquarters responsible for operational planning, policy and strategy formulation of a Navy. They are appointed to advise, assist, coordinate and supervise large scale navy activities. They make one element of a Military Staff.
In the United Kingdom the term 'Naval Staff' did not mean all naval Officers serving in the former Department of Admiralty was the government department that ran the British Royal Navy, it meant the Chief of Naval Staff, including his deputy, vice and assistant chiefs of naval staff charged with the formulation of naval strategy including strategic planning, conduct of operations, implementation of naval policy, application of tactical doctrines, the collection and dissemination of intelligence and for stating the broad naval requirements, including the quantities and specification of ships, naval aircraft, armament and equipment the Naval Staff also included some civilian members.
To achieve this the chief of naval staff established specialist functional directorates, divisions, sections and departments focused on: air, anti-submarine activities, communications, personnel, plans, policy, gunnery, intelligence, local defence, logistics, mercantile movements, operations, signals, trade, training and warfare, which they controlled and directed.