It has been twenty-five years since ground-based radar profilers were first demonstrated as capable of providing continuous wind information in the lower and middle atmosphere. Today, Doppler radar profilers are in routine operation in many countries around the globe as part of the operational observational network. They are also used in field campaigns to provide continuous measurement of winds above the surface and for other diverse applications in atmospheric science including precipitation research. This paper reviews the development of radar profiling of the atmosphere from the earliest days of proof of concept to the modern application of profiler observations for operational use for assimilation into meteorological models.