OCHA - Relief Web (United Nations Office for the Coordination of Humanitarian Affairs - Geneva)
OECD (Organization for the Economic Cooperation and Development - Paris)
OHIM (Office for the Harmonization of the Internal Market - Alicante, Spain)
OHR (Office of the High Representative for implementation of the Bosnian Peace Agreement - Bosnia)
OHRM (Office of Human Resources Management of United Nations)
OIE (Office International des Epizooties -World Organization for Animal Health - Paris)
OPCW (Organization for the Prohibition of Chemical Weapons - The Hague)
OPEC (Organization of Petroleum Exporting Countries, Vienna, Austria)
OSCE (Organization for Security and Co-operation in Europe - Vienna)
OSHA (European Agency for Safety and Health at Work - Bilbao)
