The challenge of observing the Earth’s thermal emission to space with both broad spectral coverage and high spectral resolution was laid down by the successful IRIS (Michelson interferometer) and SIRS (grating spectrometer) satellite sensors aboard Nimbus 3 in 1969. In the late 1970’s and early 1980’s, the idea of improving the vertical temperature and moisture profiling capability of meteorological satellites with the use of high spectral resolution infrared observations was proposed as the High-resolution Interferometer Sounder (HIS) concept. Seventeen years after the IRIS measurements, the University of Wisconsin, with the support of NOAA and NASA, demonstrated the new HIS sounding concept by making high spectral resolution infrared observations with broad spectral coverage from the high altitude NASA ER-2 aircraft. Seventeen years after the first HIS aircraft flights, the AIRS sensor on NASA’s Aqua platform was launched to demonstrate the value of having high spectral resolution infrared observations on a global scale for use in numerical weather prediction. This paper charts the course of high spectral resolution infrared sounding from the time of the early pioneering efforts through the current suite of satellite, aircraft, and ground-based sensors. We also look toward the future of high spectral resolution infrared observations as the NPP CrIS and NASA GIFTS sensors provide a path to operational polar (NPOESS) and geostationary (HES) observations.