Collision-induced absorption coefficients for the 1.27 μm band of O2 have been measured at a resolution of 0.5 cm-1 and an optical path length of 84 m using a Fourier transform spectrometer. Spectra were recorded for sample densities &rgr; from 1 to 10 times that of an ideal gas under standard conditions (T=273.15 K and P=101.325 kPa) at temperatures of 253, 273, and 296 K for pure O2 and O2/N2 mixtures. After removing the contributions from the sharp lines of the v=0←0 component of the O2a1Δg←X3&Sgr;g- band, which overlaps the continuum band, the integrated band strength per unit path length, S≡SO2-O2&rgr;O22+SO2-N2&rgr;N2&rgr;O2, has been determined for several values of the densities, &rgr;O2 and &rgr;N2, to give values for SO2-O2 and SO2-N2. At 296 K we find SO2-O2=4.847(22)¿10-43 cm-2 (molecule/cm3)-2 and SO2-N2=0.941(50)¿10-43 cm-2 (molecule/cm3)-2. Type A standard uncertainties are given, that is, ¿1&sgr;, from a least squares analysis of the integrated-intensity-versus-density data. The SO2-O2 coefficient is in reasonable agreement with the previous measurements of Cho et al. <1963>; however, our value for SO2-N2 is 2.6 times greater than their results. Our derived air coefficient SO2-air is 37% greater than the atmospheric value of Mlawer et al. <1998>, after correcting their continuum value for an updated value for the absorption coefficients for the overlapping discrete structure of the O2a1Δg←X3&Sgr;g- band. ¿ 1999 American Geophysical Union