The document presents the AIS and MET data link services that are envisaged to be implemented within the next decade in both the USA and Europe. It is presented in an Operational Service and Environment Definition (OSED) form@ which is based on the criteria set forth in RTCA DO-264 / EUROCAE ED-78A - Guidelines for Approval of the Provision and Use of Air Traffic Services Supported by Data Communications. The OSED describes the intended AIS and MET data link services and the assumptions about the environment in which they operate. It intends to provide the aeronautical information for pilot decision support and Collaborative Decision Making (CDM) between ground services@ the flight deck@ Air Traffic Control (ATC) and@ as appropriate@ Airline Operations Centers (AOCs) in all flight environments for flight efficiency and/or hazard avoidance.