The CubeSat Radiometer Radio Frequency Interference Technology Validation (CubeRRT) mission developed and deployed into orbit a 6U CubeSat to demonstrate radio frequency interference (RFI) mitigation technologies in support of future microwave radiometry missions. Microwave radiometers observe Earth’s natural thermal emissions and make important contributions to observing Earth’s atmosphere, oceans, and land surfaces including products such as atmospheric water vapor, temperature profiles, sea surface wind speed and direction, soil moisture, sea ice properties, and other products. Microwave radiometer measurements below 40 GHz exhibit increasing man-made RFI, having a degenerative impact on these important geophysical retrievals and potentially degrading the capabilities of future radiometer missions. To address the growing RFI problem, the CubeRRT mission was selected under the In-space Validation of Earth Science Technologies (InVEST) program, managed by NASA’s Earth Science Technology Office, to demonstrate on-board, real-time RFI processing from 6-40 GHz. Led by The Ohio State University with collaborators at Goddard Space Flight Center, Jet Propulsion Laboratory, and Blue Canyon Technologies, the CubeRRT mission provided important operational data that will inform future RFI mitigation system designs. This talk summarizes CubeRRT’s design, development, and integration on an aggressive two year schedule, followed by a year and a half period of operations and data acquisition. We highlight a variety of valuable lessons learned that can benefit future CubeSat missions.