There are currently four main CRSs: SABRE (American Airlines); APOLLO (United Airlines); AMADEUS (AF, SAS, Lufthansa, Iberia); and GALILEO (BA, KLM, TAP, Sabena, Swiss Air, Alitalia, Aer Lingus).
Les principaux SIR sont actuellement au nombre de 4, SABRE (American Airlines), APPOLO (United Airlines), AMADEUS (AF, SAS, Lufthansa, Iberia), GALILEO (BA, KLM, TAP, Sabena, Swiss Air, Alitalia, Aer Lingus).