Recent developments in near infrared detectors and electronic readouts allow improvements in the sensitivity of near infrared spectrometers by nearly a factor of 100. Under this award, two instruments will be built to realize this advance, one at ambient temperature and the other cooled cryogenically. Together, the instruments should operate at the back-ground limit set by OH (Hydroxide) airflow or telescope thermal emission from 1 to 2.5 microns; these are the fundamental limits to the sensitivity in this spectral region. The extension of the operating range to 6 microns will be investigated. The spectrometers will provide versatile capabilities for studies of the surfaces of planets and satellites in the outer solar system, low luminosity stars, brown dwarfs, star formation, processes in the interstellar medium, our Galactic Center, stellar populations in other galaxies, star formation in starburst galaxies, and the state of the gas in active galaxy nuclei.