Sabre, Travelport (the majority owner of Galileo, Apollo, and Worldspan), and Amadeus represent the leading GDSs today.
Different corporations partner with different GDSs, so each system connects agents to their own set of participating vendors. For example, Sabre can be used to book flights with American, JetBlue, Cathay Pacific, and China Air, among a host of major airlines, as well as hotel rooms from chains like Kimpton Hotels & Restaurants, Preferred Hotel Group, and others. Amadeus, on the other hand, works with British Airways, Southwest, Qantas, Lufthansa, and more. As the corporate landscape keeps shifting, however, some travel retailers have cut deals with several different GDSs simultaneously, allowing certain aspects of their services to be accessed through multiple channels.