We compare wind speeds derived from microwave radiometer measurements made by the Special Sensor Microwave Imager (SSM/I) series of satellite instruments to those directly measured by buoy-mounted anemometers. The mean difference between SSM/I and buoy winds is typically <0.4 m s-1 when averaged over all operational Tropical Atmosphere-Ocean and National Data Buoy Center buoys for a given year, and the standard deviation is <1.4 m s-1. Mean errors for a given satellite-buoy pair typically range from -1 to +1 m s-1, with standard deviations <1.4 m s-1. Two methods of converting buoy-measured wind speed to a standard value measured at a height of 10 m are compared. We find that the principal difference between a simple logarithmic correction and a more detailed conversion to 10 m equivalent neutral stability wind speed is a shift of wind speed by about 0.12 m s-1 with no change in the distribution of SSM/I-buoy wind speed differences. ¿ 2001 American Geophysical Union