This report covers collection of pavement conditions and other pertinent performance data for 6 representative pavement sites that have failed prematurely and 2 sites which have performed as intended. Interviews of Oklahoma DOT personnel, 1 review of records, inspection by an expert diagnostic team together with a field data collection program are also included. Based upon this data as well as laboratory testing and analysis of the deflection testing performed, an assessment of the causes for early failures at the representative sites are made. Recommendations for changes in design and construction practices to prevent future premature pavement failures are included.