Auroral observations of the O I (7990 ¿) multiplet intensity distribution have been performed using a 2-m grille spectrometer and a Fabry-Perot interferometer in Alaska during 1977 and 1982, respectively. In addition, an extensive set of 1-m and 1/2 -m Ebert-Fastie spectrometer data obtained at Poker Flat, Alaska, and Longyearbyen, Svalbard, from 1977 to 1980 has been analyzed. The grille spectrometer results for the singlet/doublet ratio of the O I (7990 ¿) multiplet indicate a nonstatistical distribution in the excited state, consistent with preferential scattering of the singlet component of the O I (989 ¿) EUV emission and in accord with recent radiative transfer calculations (Meier, 1982). The striking departure of the Fabry-Perot results from the model may be due to blending of the O2(4, 4) band with the O I (7990 ¿). Complete absorption of the EUV doublet by N2 is precluded by the clear presence of the O I (7990 ¿) doublet component in the auroral spectrum. A comparison of O I (7990 ¿) intensities measured on the nightside with those from dayside magnetospheric cleft aurora shows a cascade contribution to the O I (8446 ¿) line and ultimately the O I (1304 ¿) transition that depends on the altitude of the aurora. This is attributed to the greater radiative entrapment of O I (989 ¿) at low altitude and corresponding enhanced probability for branching from the 3 s' to the 3 p level in atomic oxygen.