The Geometric Archetype Design System (GADS) is intended to be used as an interface to the Thermal Radiation Analysis System (TRASYS) and the Simplified Space Payload Thermal Analyzer (SSPTA) programs. Technological advances in computer software and hardware during the last few years has provided the capability for developing versions of TRASYS and SSPTA that run on personal computers. GADS was designed to assist spacecraft thermal design engineers in generating and viewing TRASYS and SSPTA geometric math models. GADS is an object oriented program written for Microsoft Windows 3.1 with the intention of supporting Windows 95 and Windows/NT.GADS uses state-of-the-art numerical methods for fast and accurate geometric model generation. The Windows 3.1 user interface provides a familiar and user friendly working environment.