A plan was developed for evaluation of the relationship between ride and ride quality of vehicles currently used in public transportation systems and new prototypes. The components of ride as the physical environment and ride quality as passenger response were defined and articulated. Three settings were recommended for conduct of research: a simulator, rides by captive passengers, and rides by revenue passengers. A procedure was described for the implementation of experimental studies. Key features involved accumulations of a growing data bank describing ride-ride quality relationships and forecasting results of future experiments from the data bank. An experiment was conducted in the NASA Langley simulator to examine the relationships between ride vibrations derived from actual railway track signatures and ride quality as rated by subjects. When the design was replicated, comfort ratings by subjects were highly reliable. Subjects could discriminate between stimulus amplitudes for continuous rough track and diamond crossings; they could not discriminate amplitude variations well for roll. These data fail to show that subjects can discriminate well between the different types of vibration that define ride.