Description / Abstract: This document addresses the phased implementation process of the ADLS beyond Build 1A in all operational domains and phases of flight. It focuses on Build IIA for domestic en route and Build IIB for terminal area operations. Issues addressed include accommodation, transition and the development of new operational services using data link and integration with ATS decision support tools. It also describes the aviation community consensus regarding the evolution and implementation path for the provision of ATS over ATN in the NAS.