Collisional relaxation of the coupled nu(3), nu(1) stretching modes of O-3 at 90 K has been investigated by monitoring time and pressure variations of the infrared emission at 9.6 mu m. Spectral modeling was utilized to determine the temporal variations in the populations of each vibrational level. A single quantum collisional relaxation model was used to evaluate total decay rates out of each vibrational level in this highly coupled system. Total decay rates at several different pressures were subjected to a Stern-Volmer analysis and have yielded level specific rate coefficients for collisional quenching of O-3 With UP to three vibrational quanta. Quenching rate coefficients were found to be in the range of 10(-14)-10(-15) cm(3) molecule(-1) s(-1) for O-2, N-2, and Ar collision partners. Vibrational Einstein coefficients for O-3(nu(3)) With UP to three quanta were also determined. This represents the first experimental determination for the two- and three-quanta states. These Einstein coefficients compare favorably with detailed theoretical predictions.