Our geodetic VLBI group at the Goddard Space Flight Center was constituted in 1974 and has been active ever since. The earliest VLBI data in our archives were taken in 1972 with the Mark I VLBI system. In the analysis of these data the formal errors in the length of 4000-km baselines spanning the U.S. are typically 70 mm. Today - ∼25 years later - with the Mark IIIA VLBI system we are obtaining formal errors under 1 mm for the best comparable baselines. There have been similar improvements in the estimates of UT1 and polar motion based on VLBI. These improvement came about as a result of continuous improvements in data acquisition hardware, correlators, experiment planning and data analysis. Geodetic VLBI has produced numerous important scientific results. It has verified that the motions of the stable plate interiors are in very good agreement with motions predicted by plate motion models based on data sensitive to effects on the geologic time scale. It has shown that there are broad regions of deformation along the plate boundaries and it has detected discontinuous motions associated with earth-quakes. The Earth orientation results showed that space geodetic techniques could completely replace classical techniques for monitoring Earth orientation. Earth orientation results from VLBI have been used to study the Earth's core/mantle interface and ocean tidal currents. Starting in 1999 our group will be a part of an international consortium measuring Earth orientation on a continuous basis with 24-hour observing sessions scheduled every day and using the Mark IV VLBI system.