Rufenacht is recognized for extraordinary innovation in the development and widespread adoption of the NIST Programmable Josephson Voltage Standard reference instrument. His direct development of instrumentation, software, best practices and user interface, and his proactive interactions to solve customer problems, has enabled this revolutionary voltage standard to be used by 13 national metrology institutes and industrial standards laboratories worldwide for the calibration of voltage standards, precision voltmeters, force and power meters. The self-calibrating standard reference iInstrument allows direct realization of SI voltage with quantum accuracy. Rufenacht's contributions helped enable the redefinition of the SI.