Travelport is a global distribution system operator. Travel suppliers place content on the GDS platform, which is then used by traditional travel agents, travel management, and online travel agencies to book travel. Travelport, Sabre, and Amadeus combine for 98% share of the GDS market. International markets made up 74% of revenue in 2018 with U.S. markets representing the other 26%. Transaction fees, which are tied to volume and not price, account for the bulk of revenue and profits.