In 1964, the U.S. Weather Bureau's National Severe Storms Project (NSSP) moved from Kansas City to Norman and changed its name to the National Severe Storms Laboratory (NSSL). For the next 25 years, NSSL continued NSSP's (and its predecessors') long-standing tradition of improving understanding of severe storms by conducting a data collection program each spring that included surface and upper air mesonetworks, research aircraft, and radars. Over the years, Doppler radars (including dual polarization), an instrumented TV transmitter tower, storm intercept teams, and storm electricity measurements were added. In more recent years, spring programs have become more intermittent because of funding constraints, with many associated with national research programs (involving airborne Doppler radars) in the southern Plains. Since the early 1990s, various NSSL sensors have become mobile with the addition of mobile rawinsonde release vehicles, balloon-borne storm electricity sensors, mesonetwork instruments on the tops of cars, and Doppler radars on the backs of trucks. Early NSSL research has had a positive impact on improved public safety. Aircraft studies of turbulence in severe thunderstorms, called Project Rough Rider, during the 1960s, 1970s, and early 1980s led to improved commercial airline safety guidelines in the vicinity of thunderstorms. NSSL Doppler radar studies of thunderstorm mesocyclones and tornadoes during the 1970s led to the decision by the National Weather Service (NWS), U.S. Air Force's Air Weather Service, and Federal Aviation Administration (FAA) to include Doppler capability in their updated operational WSR-88D and Terminal Doppler Weather Radar networks. The WSR-88D has helped forecasters significantly improve severe thunderstorm and tornado warnings, saving countless lives. NSSL continues to support the NWS and FAA by developing and refining radar algorithms for identifying severe weather phenomena and estimating precipitation accumulations, and by helping to design better radar acquisition and processing equipment. A program is currently underway to collect data much faster using a newly-constructed phased array Doppler radar. By the mid 1980s, NSSL was developing an expertise in numerical modeling. Various techniques, including ensembles, are being investigated to improve the numerical prediction of storm-scale, mesoscale, and synoptic-scale processes. In 1997, soon after the National Severe Storms Forecast Center in Kansas City changed its name to the Storm Prediction Center (SPC), it moved to Norman. With the SPC being collocated with NSSL, there have been many opportunities for NSSL meteorologists to help SPC forecasters develop improved severe storm forecasting techniques, including the application of probabilistic forecasting techniques. Thus, through its various research activities during the past 40 years, NSSL has been instrumental in advancing the state of the art of severe storm detection and prediction.