CentREZ International
- Provides hotel members GDS and IDS representation to Amadeus, Galileo, Sabre, and Worldspan.
- http://www.centrez.com/

GenaRes Worldwide Reservations Systems
- Worldwide hotel reservation services provide GDS connections to Sabre, Apollo, Worldspan and Amadeus. Call center and web booking engine services also available.
- http://www.genares.com

Sabre GDS
- The Sabre global travel distribution system.
- http://www.sabre-holdings.com/

Amadeus GDS
- The Amadeus global travel distribution system.
- http://www.amadeus.com/

Pegasus Solutions, Inc.
- Provides transaction processing and electronic commerce services to the hotel industry worldwide.
- http://www.pegs.com/

REZlink International, Inc.
- Provides interface with GDS distributors, real-time reservation technology, and central reservation system products.
- http://www.rezlink.com/

InnPoints Worldwide
- Offers hotel marketing support, internet hotel reservation software, voice reservations and is a GDS provider for unique and boutique lodging.
- http://www.innpoints.com/

WorldRes
- Connects member hotels worldwide with travelers via a global network of partner websites and call centers.
- http://www.worldres.com/

InnoSys Inc.
- Provides GDS/CRS/airline host connectivity solutions, including gateways (TCP/IP, ALC, X.25), API, workstation, and printer software.
- http://www.innosys.com/

GENESIS Travel Distribution System
- A travel agency initiative to strengthen the travel distribution system and to launch the GENESIS Project, a re-engineering of the reservations, ticketing, settlement, and accreditation relationships between travel agents and air carriers.
- http://www.genesistds.com/

Infini
- Japanese CRS provider of travel information and services to the travel industry.
- http://www.infini-trvl.co.jp/

Axess
- Japanese central reservation system. Features products, services, and news. In Japanese and English.
- http://www.axess.co.jp/

WizCom International, Ltd.
- Provider of Global Distribution Systems (GDS) and internet connectivity, Central Reservations Systems (CRS) and information services to the hotel, car rental and tour industries.
- http://www.wizcom.com/

Worldspan GDS
- The Worldspan global travel distribution system.
- http://www.worldspan.com/

Galileo GDS
- The Galileo global travel distribution system, also known as the Apollo system in North America and Japan.
- http://www.galileo.com/

Abacus CRS
- Provides Computer Reservation System (CRS) services specially tailored for customers in the Asia-Pacific market.
- http://www.abacus.com.sg/

HEDNA - Hotel Electronic Distribution Network Association
- International not-for-profit trade association formed by hoteliers to promote the booking of hotel rooms through the use of Global Distribution Systems (GDSs), the Internet and other electronic hotel reservation methods.
- http://www.hedna.org/