This document outlines telecommunications service provider and customer installation and maintenance responsibilities for Switched Access Services (SAS) as established by the NGIIF and includes Telecommunications Service Priority (TSP) Guidelines. It includes procedures on installation and maintenance of trunk side connected Access Services Feature Groups (FG) B, C and D. It specifically includes areas such as NXX Code Openings, FG D CIC Testing, Network Modification Notification, Trouble Detection Responsibilities, Trouble Reporting Procedures, 500/800/900 NXX Services, Toll-Free Database and LIDB Services Trouble Handling, and access services provided by multiple exchange carriers. Where applicable, this document may address Next Generation Network (NGN) aspects.