Traffic signals are one of the primary constraints on corridor capacity in the highway/arterial network. The extent to which through traffic is impeded is heavily dependent on the quality of the signal timings. Poor signal timings can result in significant congestion that could otherwise be avoided, or at the very least minimized. The results of congestion typically include driver delay and frustration, increased air pollution, wasted fuel, and lost productivity. The concept of traffic signal optimization is one that has received significant attention from the research community. It is recognized that timing traffic signals in corridors is a multi-objective problem, in which optimizing the solution to one variable can often work to the detriment of another. As such, for any given problem, there are numerous alternatives which can be generated for consideration. To that end, improved algorithms and optimization procedures are constantly being developed, each aimed at providing analytical tools or field equipment that if implemented, will improve travel conditions on the major corridors without serious detriment to the minor traffic flows. The purpose of this research was to develop and use the Sim Traffic microsimulation model in the assessment of signal timing alternatives on a congested corridor. The simulation model was used to assess four signal timing alternatives to improve operations in the congested corridor of SR 0021 between Daniel Drive and Santa Maria Drive/Uniontown Mall drive in South Union Township, Fayette County, Pennsylvania. Findings of the engineering analysis and simulation surprisingly indicated that the benefits of progression provided by coordination were far outweighed by the costs incurred through the reduction of flexibility at the critical two-intersection system at the Cherry Tree Lane and Matthew Drive intersections when semi-actuated control with a fixed cycle length was imposed, unless the capacity-problems at the two-intersection system were resolved. This research made contributions both in the development of a methodology to accomplish such a project, and in the actual engineering analysis of signal timing alternatives for the corridor.