Foursquare ITP assisted in the evaluation of the effectiveness of transit signal priority (TSP) on several corridors in Washington, DC. For the first phase of the project, our team conducted a before-and-after analysis of bus running times, on-time performance, and speeds on three major corridors and in the downtown area to determine the effect of TSP on them. Our team then recommended changes to the TSP parameters to increase their effectiveness. Phase 2 of the project re-evaluated the same datasets to determine whether the changed parameters improved bus performance. We processed, analyzed, and visualized large datasets of bus running times, speeds, and on-time performance, then created an automated process to ensure replication would be easy.