From wiki.opentravel.org

[edit] Welcome to the OpenTravel Workgroups Page!

• Questions about OpenTravel Workgroups? send an email to the OpenTravel Specification Manager

Architecture Workgroup Page	Travel Integration Workgroup Page
Serving: All aspects of the OpenTravel specification which are outside the contents of the XML messages themselves	Serving: Companies that provide services to the travel industry & other verticals that don't functionally fit in either the Transport or Hospitality Workgroups

Transport Workgroup Page	Hospitality Workgroup Page
Serving: Air, Car and Rail verticals	Serving: Hotel and Cruise verticals