RSO

RSO or R.S.O. may refer to:

== Roles and titles == Range safety officer, a person responsible for the safe use of rocket vehicles Radiation Safety Officer, a person responsible for the safe use of radiation and radioactive materials Regional Security Officer, a Diplomatic Security Service Special Agent in charge of security at a US embassy Regional Security Office, office in a US embassy or consulate for the Diplomatic Security Service '', Knight of the Order of the Sword Reconnaissance systems officer, operator of surveillance systems and equipment on a Lockheed SR-71 Blackbird aircraft