The diverging diamond interchange (also known as a double crossover diamond interchange) is a relatively new design to the United States. This design can increase throughput and safety without widening bridge structures. The TRB National Cooperative Highway Research Program's NCHRP Research Report 959: Diverging Diamond Interchange Informational Guide, Second Edition presents a comprehensive guide to the design and operation of diverging diamond interchanges and updates material found in the FHWA's Diverging Diamond Interchange Informational Guide. A workshop summary is provided that includes an overview of key traffic signal timing concepts at diverging diamond interchanges--from terminology to timing considerations and from operational analysis to traffic signal equipment. Videos viewed during the workshop are also provided.

Management of traffic signal systems is a critical function for every transportation agency. Thanks to advancements in technology, it is now possible to collect large amounts of data at signalized intersections, leading to the development of dozens of performance measures. The TRB National Cooperative Highway Research Program's pre-publication draft of NCHRP Research Report 954: Performance-Based Management of Traffic Signals provides information to help agencies invest in signal performance measures as part of a comprehensive approach to performance-based management. Supplementary materials to the report include a data dictionary and a PowerPoint presentation.