Long-Term Pavement Performance Studies The Long-Term Pavement Performance program (LTPP) is the largest pavement performance research program ever undertaken, gathering data from 2,000 pavement test sections over a 20-year test period. The Federal Highway Administration (FHWA) has operational responsibility for the studies and maintains a resource web site for current and historical information. With more than a decade of data collection and analysis now available, valuable insights, innovations, and products will emerge from the LTPP studies in the next several years. What has been accomplished so far and what is needed to realize the promise of the 20-year LTPP effort are identified in Fulfilling the Promise of Better Roads: A Report of the TRB Long-Term Pavement Performance Committee.