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

Organisations

  • "Radio Symphony Orchestra", used by a number of orchestras:
  • Danish National Symphony Orchestra, based in Denmark
  • North German Radio Symphony Orchestra, based in Hamburg, Germany
  • Stuttgart Radio Symphony Orchestra, based in Stuttgart, Germany
  • Bavarian Radio Symphony Orchestra, based in Munich, Germany
  • Frankfurt Radio Symphony Orchestra, based in Frankfurt, Germany
  • Finnish Radio Symphony Orchestra
  • Swedish Radio Symphony Orchestra
  • Vienna Radio Symphony Orchestra
  • Richardson Symphony Orchestra, based in Richardson, Texas
  • Roanoke Symphony Orchestra, based in Roanoke, Virginia
  • Rogers Sportsnet Ontario, a television station in Ontario, Canada
  • RSO Records, a record label formed by Robert Stigwood in the late 1960s

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  • Rohingya Solidarity Organisation, a political organization and former insurgent group in Myanmar (Burma)

Military technology

  • Raupenschlepper, Ost, a fully tracked World War II German artillery tractor
  • Radschlepper Ost, a wheeled World War II German artillery tractor

Other

  • Railway Sub Office (1855–1905), a British Royal Mail office which received mail directly from rail transport
  • Reactive Search Optimization, problem-solving methods with integrated online machine-learning capabilities
  • Revised Statutes of Ontario, the provincial laws of Ontario, Canada
  • Registered sex offender, a person listed on a sex offender registry
  • Republic of South Ossetia, a partially recognised country in the South Caucasus
  • Resident Space Object, any man-made object in Earth orbit no longer used by anyone
  • Ryan Scott Oliver, an American musical theater songwriter
  • RSO, musical duo consisting of American musician Richie Sambora and Australian musician Orianthi
  • Rick Simpson Oil, a form of cannabis concentrate
  • Red Star OS, also abbreviated as RSOS, is a North Korean operating system