Trends in RF performance requirements for contemporary spacecraft are driving vehicle design to achieve extremely low RF emissions levels due to unintentional sources. This paper describes an approach to achieving very low spurious RF emissions in spacecraft by identifying, predicting and controlling emissions sources during architecture development. The approach incorporates detailed, tailored analysis and test methods used to verify performance compliance. Specific test results are discussed in the context of showing the effectiveness of this design approach in meeting tailored MIL-STD-461E radiated emissions limits.