Australian Railroad Group
The Automated Reasoning Group. A research group looking at theorem provers.
German pipeline group, major ethylene inland distribution (Aethylen Rohrleitungs Gesellschaft)
Accident Response Group, a DoE volunteer unit that responds to nuclear accidents. See also NEST
Ada Rapporteur Group. A subgroup of ISO/IEC/JTC1/SC22/WG9, the International Organization for Standardization Working Group for Ada. Members of the ARG are appointed by the convener of the ISO working group for the purpose of resolving issues with respect to the interpretation of the Ada programming language.
Air Refueling Group (USAF)