Chief Petty Officer, or C.P.O., is a non-commissioned officer or equivalent in many naval services, coast guards and space exploration agencies. In the United States Navy and Coast Guard, Chief Petty Officer is the seventh enlisted rank just above Petty Officer First Class and below Senior Chief Petty Officer, and is a senior non-commissioned officer. In the Royal Navy, the rank of Chief Petty Officer comes above that of Petty Officer and below that of Warrant Officer Class 2. It is the equivalent of Colour Sergeant in the Royal Marines, Staff Sergeant in the Army, and Flight Sergeant in the Royal Air Force.