NASA's National Aeronautics and Space Administration is seeking ongoing maintenance and upgrades for the Numerical Propulsion System Simulation® (NPSS®) software, which is crucial for analyzing thermodynamic systems in advanced propulsion and power applications. The procurement aims to ensure the software's continued capability and is aligned with a 2010 Software Use and Distribution Agreement with the Ohio Aerospace Institute, offering services at a pricing structure available to the lowest-tier NPSS consortium members. This initiative emphasizes collaboration within NASA's software development framework and reflects the agency's commitment to advancing technology in propulsion systems. Interested organizations with the capability to perform the required work must submit their qualifications in writing by 4:00 p.m. Central Standard Time on March 12, 2025, to Lindsey McLellan at lindsey.m.mclellan@nasa.gov.