This report was prepared as part of the Rail Supporting Technology Program sponsored by the Office of Research and Development, Rail Programs Branch, of the Urban Mass Transportation Administration. Rail fasteners for concrete ties and direct fixation and bolted rail joints have been identified as key components for improving track performance. However, the lack of statistical load data limits the development of improved design criteria and evaluation tests. This report evaluates the data required for design, laboratory tests, and for the development and verification of analytical models of fastener and joint performance. Available track instrumentation is reviewed for fulfilling these requirements, and functional specifications have been developed for improved tie plate load cells and instrumented wheels. Also included are recommendations for data analysis and data processing procedures and test site selection criteria needed to plan and conduct comprehensive measurement programs.