The Chief of the Hellenic National Defence General Staff () conducts the HNDGS and is the main adviser to the Government Council for Foreign Affairs and Defence (KYSEA) and to the Minister of Defence on military issues.
Through the Chiefs of General Staffs, he carries out the operational commanding of the Joint Headquarters and the units that come under them, as well as the rest forces, when it comes to the issues of operation plans implementation and the Crises management System implementation, conduction of operations outside the national territory and participation of the Armed Forces in the confrontation of special situations during peace time.