This report presents the results of an acoustical scale modeling research effort in which the performance of special noise barrier shapes is compared to the performance of conventional noise barriers. This effort is a follow-up to previous work (Phases I and II) in which various barrier shapes were examined for increased performance and cost-saving potential. The results of this study provide generally good agreement with the results predicted by the Phase II project. While not exactly reproducing the theoretical performance of the special barrier shapes, this scale modeling effort has demonstrated that an increase in performance can be expected by implementation of these special barrier shapes. The report concludes that while these special barrier shapes did not provide the magnitude of insertion loss expected, the results do indicate an increased barrier performance using them. A recommendation for implementation of the special noise barrier shapes on specific actual projects is then made.