This paper presents a case study of the Radiation Belt Storm Probes (RBSP) mission Command and Data Handling (C&DH) Flight Software stress testing program. Background information on the motivation for stress testing embedded software, and the general principles and goals of a stress test are provided as an introduction. Details of the stress test program that was implemented for the RBSP C&DH Flight Software are presented and discussed. This discussion includes the design and development of a test framework that was implemented to incrementally build the test scenarios, increase the productivity of the RBSP stress test team, and facilitate reuse for regression testing. Results of the RBSP stress test program are summarized, and lessons learned that may be useful for future embedded software test programs are documented.