Detailed results of a two-year study of lime and liquid treated asphalt from five states. Typically, lime and liquid are used as additives to combat moisture damage. This study extended the evaluation to cover the impact of lime and liquid additives on the structural performance of the HMA mixtures and their impact on the long term performance of typical HMA pavements. This study shows that lime significantly improves the cracking resistance of asphalt mixtures, while the use of liquid additives may jeopardize the cracking resistance of asphalt mixture. The results also demonstrate that lime always improves pavement performance and lowers cost compared to liquid for both new roads and repairs/overlays. (Full report: 135 pp)