Efficiency and life requirements of advanced turbomachinery and the pollution demands of the Clean Air Act dictate the need for significant advances in seal technology *. NASA is sponsoring a program to produce computer codes to be used by industry and government for analyzing and designing a wide variety of advanced seals for rotating machinery. A general computational fluid dynamics (CFD) code is being generated for accurate flow simulations, as well as simpler 2-D codes for expeditious application. A knowledge-based system (KBS) controls the codes and includes a user-friendly graphical user interface (GUI). A data base and an expert system to provide design guidance to the user will be added. This paper describes the codes and their application.