GDS (Global Distribution System)

The three major GDSs are Amadeus, Sabre, and Travelport. They connect airlines, hotels, rental car companies, and rail operators to travel agencies and corporate booking tools, showing live availability, fare rules, and seat maps in one place. A booking made through a GDS creates a passenger name record (PNR) that the agency can see and service.

That visibility is the practical advantage for travelers. When a flight cancels or a meeting moves, an advisor working in the GDS can see the whole itinerary, check the fare rules, and rebook or reissue the ticket instead of leaving you on hold with an airline. Corporate travel programs also rely on GDS data for traveler tracking and spend reporting.

The landscape is shifting. Many airlines now distribute some fares through direct NDC (New Distribution Capability) connections, and some low-cost carriers sell mainly through their own websites, so a good advisor checks more than one source before booking.