The purpose of this project is to understand why public involvement in transportation project planning sometimes fails to reach a resolution that is acceptable to both the agency and the public and to determine how the process could be modified to reduce the likelihood of this outcome. A case study of a very complex and ultimately unsuccessful public involvement effort is described. This is used as the primary data source for development of a prototype of a general model of conflict management. It is concluded that there are a small number of independent dimensions around which conflict can arise and that some projects by their nature have a higher level of potential for conflict around one or more of these dimensions. The conclusion is that each of these dimensions needs to be analyzed and the likely level of conflict identified before the public involvement process begins and that the process should be explicitly structured to focus on addressing and resolving the high-conflict areas first. How public involvement efforts can be modified to better manage specific types of conflict and achieve mutually acceptable results is also described.