Freeway simulation is gaining increasing acceptance and popularity as a tool for evaluating freeway improvement alternatives and refining freeway designs. The evaluation of individual sections one at a time is frequently inadequate to fully consider the implications of traffic flow on freeway design and operations. As the need to evaluate the interaction among sections and facilities increases, so too will the need to employ these more sophisticated analytical techniques. Several freeway simulation models now operate on microcomputers, simplifying the use of the models and opening up opportunities to many engineers previously unable to take advantage of the analysis power these models afford. The purpose of this research contract, entitled "Analysis of Complex Congested Corridor Locations," was to apply three freeway simulation models and the procedures in the 1985 Highway Capacity Manual to real-world situations. Each of the models was applied in five case study sites: Seattle; Minneapolis; Milwaukee; Columbus, Ohio; and New York City. The Application of the models provided the opportunity to compare their strengths and weaknesses, to suggest possible enhancements to the models evaluated. These included FREFLO, a macroscopic simulation model developed under Federal Highway Administration (FHWA) contract; FREQ, a macroscopic model developed by the University of California at Berkeley; and FRESIM, a microscopic model developed under FHWA contract. This report is directed toward existing and potential users of freeway simulation models, with an emphasis on guidelines for model selection and application.