Global Distribution System (GDS)

A Global Distribution System, or GDS, is a computer system used to manage bookings for flights, hotels, car rentals, and other travel activities. The GDS provides travel agents access to availability and prices in order to construct an itinerary for the traveler.

There are three main companies that operate GDSs; Amadeus IT Group, Sabre Corporation, and Travelport. Combined, these companies process and transact around 45% of all flights globally.

Historically, GDSs have run centralized mainframes using legacy programming languages such as COBOL. Given the need to scale operations, there have been many attempts to re-platform as much infrastructure to cloud platforms as possible.

To demonstrate the scale of the infrastructure, Sabre’s GDS processes approximately 700 billion transactions per year.
Travel Agents typically use the GDS to build an itinerary for the traveler based on their needs and, in the context of business travel, within the confines of the business travel policy. 

Newer technologies called OBTs (Online Booking Tools) have been designed as self-service booking tools similar to or but for the corporate traveler.