The transformation of airline commercial processes and technologies to an environment based on Orders rather than PNRs and tickets is now under way. Historically many airlines have acquired their central commercial systems from a single provider in the form of a Passenger Services System (PSS). This includes the core functions of inventory, reservations, ticketing and check-in. They may add other systems such as revenue management or internet booking engines which access the database of the PSS and augment its functions.

In the world of Offer Order Settle Deliver, which is also referred to as Modern Airline Retailing, some airlines will continue to buy a comprehensive service from a single vendor. However there is an expectation, not least from the standards-setting body, IATA, that it will be open to airlines to acquire technology in a modular manner and combine components from multiple vendors to create a unique commercial stack.

The purpose of this document is to identify where in the OOSD environment familiar functionality will be located. In many cases there will not be a simple one-to-one correlation between the old and the new.