The aggregate of organizations, agencies or entities that may participate, collaborate and cooperate in the planning, development, use, regulation, operation and maintenance of the ATM system.
ICAO (2005) Doc. 9854, Global Air Traffic Management Operational Concept
The various members comprising the ATM community are: the Aerodrome community, Airspace providers, Airspace users, the ATM service providers, the ATM support industry, the International Civil Aviation Organization (ICAO), Regulatory authorities and States. (same source)
Lexicon Release 2015.2