The Chief of Army Staff (COAS) has been the title of the professional head of the Nigerian Army since 1966. Prior to 1966, the title was General Officer Commanding, Nigerian Army (GOCNA). Since 1980, the post has been immediately subordinate to the Chief of Defence Staff, the post held by the professional head of the Nigerian Armed Forces. The position is often occupied by the most senior commissioned officer appointed by the President of Nigeria.