All officers of the eight uniformed services of the United States swear or affirm an oath of office upon commissioning. It differs from that of the oath of enlistment that enlisted members recite when they enter the service. It is required by statute, the oath being prescribed by Section 3331, Title 5, United States Code.[1] It is traditional for officers to recite the oath upon promotion but as long as the officer's service is continuous this is not required.[2]