Sabre (an acronym for Semi-Automatic Business Research Environment) is a computer reservations system used by airlines, railways, hotels, and other travel companies.

The system was created by American Airlines and IBM in the 1950s, after AA president C. R. Smith sat next to an IBM sales representative on a transcontinental flight in 1953. Sabre's first mainframe in Briarcliff Manor, New York went online in 1960. By 1964, Sabre was the largest private data processing system in the world. Its mainframe was moved to an underground location in Tulsa, Oklahoma in 1972.

Originally used only by American, the system was expanded to travel agents in 1976. It is currently used by a number of companies, including Eurostar, SNCF, and US Airways. The Travelocity website is owned by Sabre and serves as a consumer interface to the system.

American spun off Sabre in the 1990s; the system is now owned by an independent operator, Sabre Holdings.