The U. S. has been testing radiosonde manufacturer's radiosondes for many decades at test facilities around the country and has developed a number of test techniques for verifying performance. Recent advances in measuring the upper air atmosphere utilizing state-of-the-art referencing technologies and the development of new test techniques within the U.S. are now available for evaluating radiosonde performance to meet the more stringent climate monitoring requirements. Examples of these reference technologies include: NASA's Advanced Temperature Measuring system, LIDARs for measuring the mid-to-upper tropospheric moisture, Snow White, high-precision GPS measurements of height, the Integrated Precipitable Water sensor using GPS techniques, various radiometers, and ground-based surface instrumentation to measure clouds and weather. Each reference technology can play an important role in the Consensus Reference Concept; whereby, statistical techniques would be applied to the time-based and pressure/height radiosonde measurements of temperature, moisture variables, cloud bases, and winds as compared to the candidate reference. The meteorological and climate communities could provide a set of criteria for performing these inter- and intra-comparisons and determine the minimal variance allowed to be compliant with each reference. This approach will provide the community a wealth of knowledge in their overall performance, which can be repeated as often as necessary, and can serve as a methodology for allowing the community to come to a consensus on which candidates meet the stated requirements and where more work is needed if they fall short.