A challenge for the Arizona Department of Transportation (ADOT) will be to use a variety of practical, relevant congestion mitigation options in appropriate, collaborative and innovative ways to address current and future congestion problems. To meet this challenge, ADOT has undertaken the development of a comprehensive Congestion Mitigation Methodology for the implementation of a consistent and sustained approach to assess and manage the growing congestion problem on all elements of the state highway system. This effort has resulted in the development of practical strategies to solve Arizona's mobility and congestion problems. A significant step in the development of the Congestion Mitigation Methodology was building a consensus among traffic management stakeholders on effective definitions for congestion and for congestion management. Input on the definitions and state of the practice in congestion mitigation came from a national survey of Metropolitan Planning Organizations and State Departments of Transportation and from a statewide conference on congestion mitigation. The research project has produced recommendations for systematically quantifying congestion on Arizona's highways using a state-specific congestion index, and has also produced a database of available congestion mitigation strategies in Microsoft Access.