International Telemetering Conference Proceedings / October 20-23, 2003 / Riviera Hotel and Convention Center, Las Vegas, Nevada / As part of the National Polar-orbiting Operational Environmental Satellite System (NPOESS) Preparatory Project (NPP), the Direct Readout Laboratory (DRL) of NASA/GSFC Code 935, is developing the prototype NPP In-Situ Ground System (NISGS). The NISGS supports earth remote sensing, and its functions bridge from all EOS satellites to planning for future NASA and interagency launches. The NISGS solution enables the end user to acquire and process NPP and predecessor instrument data, and provide a means to make these technologies and data products available to the Direct Broadcast Community. This document describes the NISGS model, methodology, and system architecture.