The computing environment is briefly described for the Supercomputing Network Subsystem (SNS) of the Central Scientific Computing Complex of NASA Langley. The major SNS computers are a CRAY-2, a CRAY Y-MP, a CONVEX C-210, and a CONVEX C-220. The software is described that is common to all of these computers, including: the UNIX operating system, computer graphics, networking utilities, mass storage, and mathematical libraries. Also described is file management, validation, SNS configuration, documentation, and customer services. Tennille, Geoffrey M. and Howser, Lona M. and Humes, D. Creig and Cronin, Catherine K. and Bowen, John T. and Drozdowski, Joseph M. and Utley, Judith A. and Flynn, Theresa M. and Austin, Brenda A. Langley Research Center...