This paper is concerned with the application of wind-profiling Doppler radar technology to tropical atmospheric research. Examples of the use of wind profilers in the tropics are drawn from the Aeronomy Laboratory's wind profilers located on Pohnpei, Micronesia (7¿N, 158¿E), and Christmas Island (2¿N, 157¿W). The Pohnpei wind profiler was constructed in 1984 and has been used exclusively to observe vertical motions. The Christmas Island wind profiler has observed horizontal and vertical velocities routinely since 1986. These two wind profilers form part of a planned trans-Pacific network of wind-profiling radars that will eventually span the tropical Pacific.