The senior-most Chief of Staff acts as the chairman of the Chiefsof Staff Committee (COSC). COSC is the authority for advising theDefence Minister and normally through him the Cabinet Committee on Political Affairs on all military matters which require ministerial consideration. The COSC is composed of: (a) Chief of the Army Staff (COAS); (b) Chief of the Naval Staff (CNS); (c) Chief of the Air Staff (CAS); and (d) Chief of the Integrated Defence Staff (CIDS) (non-voting member). The Scientific Adviser to the Minister of Defence is invited to attend whenever needed. The senior-most member of COSC is appointed as its Chairman.