Alternative Distribution System

What is the definition of ADS in the hotel industry?

Alternative Distribution System, abbreviate ADS is a term used to explain the circulation via 3rd party sites.

This includes online travel agencies (OTA), travel portal, travel search engines / directories, online hotel consolidators, airline sites with online reservation options.

Examples: Expedia, Orbitz, Priceline, Hotwire,, Opodo

ADS serve as an implicit marketplace where travel record re-sellers can showcase their customers (like Hotels) to the global internet travel spectators.