[MyDogHasFleas]

AFAIK, SABRE is/was an airlines reservation system, not a GDS. SABRE evolved into TPF which is not related to z/OS except inasmuch as they are both operating systems that run on IBM z-series mainframes.

See http://www-03.ibm.com/systems/z/os/ for a list of IBM z-series operating systems.

[bdg]

I worked with SABRE -- it's a GDS, and a reason I really want to avoid the entire industry.

[ajdlinux]

SABRE is a GDS - it's used by a whole bunch of US and non-US airlines.