| AUD | Australian Dollar Währungsbezeichnung nach ISO in Australien |
| Aust. For. Res. | Australian Forest Research Zeitschrift |
| Aust. J. Ecol. | Australian Journal of Ecology Zeitschrift |
| RAAF | Royal Australian Air Force |
| AIE | Australian Instititute of Energy |
| Aust. J. Bot. | Australian Journal of Botany Zeitschrift |
| ATC | Australian Tourist Commission [engl.] |
| ANU | Australian National University [engl.] Canberra |
| AMA | Australian Mining Association [engl.] Australische Bergwerksvereinigung |
| AIS | Australian Istitute of Sport [engl.] |
| ASX | Australian Stock Exchange [engl.] Australische Börse [Börsencode] |
| RACI | Royal Australian Chemical Institute |
| ACT | Australian Capital Territory [engl.] Canberra, http://www.act.gov.au |
| AAAA | Australian Automotive Aftermarket Association Mulgrave, Victoria [Australien] http://www.aaaa.com.au |
| AIGR | Australian Institute for Gambling Research [engl.] Sydney |
| ATC | Australian Transport Council of Ministers [engl.] Australische Verkehrsbehörde |
| ASIO | Australian Security Intelligence Organisation [engl.] |
| ARIC | Australian Railway Industry Corporation [engl.] Australisches Unternehmen der Eisenbahn-Industrie |
| APCA | Australian Port Charges Additional [engl.] Zusätzliche Hafengebühren in Australien |
| AOSM | Australian Online Shopping Mall [engl.] Internet-Verkauf |
| ADFA | Australian Defence Force Academy [engl.] Canberra, [AUS], http://www.unsw.adfa.edu.au |
| ACTA | Australian City Transit Association [engl.] Nahverkehrsverband in Australien |
| AIPC | Australian Intellectual Property Cases [engl.] |
| ARHS | Australian Railway Historical Society [engl.] Australische Interessengemeinschaft für historische Eisenbahnen, betreibt das Eisenbahnmuseum bei Melbourne |
| AIMS | Australian Institute of Marine Sciences [engl.] Australisches Meeresforschungsinstitut |
| AO | Australian Airlines [IATA-Airline-Code/ Australien] |
| XM | Australian Air Express [IATA-Airline-Code / Australien] |
| ASXD | Australian Stock Exchange Derivates and Option Market [engl.] Abteilung der australischen Börse |
| OC | Open Control |
| o.c. | open cup [engl.] Flammpunktbestimmung mit offenem Tiegel |
| OS | Open Source |
| OT | Open Transport |
| OSL | Open Source Lab |
| STGO | Start Tag Open |
| XOM | X / Open Management |
| OMA | Open Mobile Architecture |
| OPI | Open to Public Inspection |
| OPI | Open Prepress Interface |
| OPL | Open Publication License |
| OPN | Open Projects Network |
| OPP | Open Publication Policy |
| OPS | Open Profiling Standard |
| OPSEC | Open Platform for Security |
| OPT | Open Protocol Technology |
| OLIT | Open Look Interface Toolkit |
| ORF | Open Reading Frame |
| OPA | Open Protocol Architecture |
| ONP | Open Networking Platform |
| OLE | Open License for Education |
| OMA | Open Management Architecture |