A Software Support Facility (SSF) designed initially for the A-6E Weapon System Trainer (WST) and located at the Naval Training Equipment Center (NAVTRAEQUIPCEN). Orlando, is seen as a significant advance in capability for updating software-intense trainers. This paper describes a software support environment that facilitates the modifications, testing, and baseline configuration management of software used in sophisticated trainers. The software support environment consolidates a variety of techniques into an effective capability for managing the implementation of modifications. Baseline configuration management is founded on the implementation of operational procedures that make it easy to adhere to configuration guidelines but difficult to get changes into the system by other means. Automated identification of global symbol generation and usage greatly reduces risk of unforeseen change impact on other routines. A trainer software structure is described that permits modification of source code without patches and without the normal complete link-edit procedure. A communication link facilitates rapid turnaround in the modification and test cycle. Potential support of trainers with different computers is identified. Further, the SSF reality makes possible the overall integrated environment of "man" and "machine" for management, control and visibility for software support.