Since late 1988, a medium-frequency radar (MFR) and an imaging Fabry-Perot interferometer (FPI) have been operating continuously at Saskatoon, measuring winds and waves in the upper mesosphere and lower thermosphere. When weather and auroral conditions permit, the FPI measures Doppler winds from the atomic oxygen OI 557.7-nm airglow layer centered at an altitude of about 97 km. This study is similar to earlier comparisons between the MFR/FPI systems except that it draws on 4 years of simultaneous observations. Because the MFR and FPI are somewhat mutually exclusive in their data acquisition rate, real-time comparisons of winds are ofter poor. However, with the much larger FPI data set now available, rather better long-term comparisons between the two systems can be made. Once again, strong similarities in the MF radar and FPI Doppler wind fields are observed, although there are some differences. These differences and the causes are discussed. ¿ American Geophysical Union 1994