President of Imbsen Consulting, Sacramento, California, has over 45 years of bridge engineering experience, the first 15 of which were spent with Caltrans, Division of Structures. A world-recognized expert in the field of seismic bridge engineering and bridge design, Dr. Imbsen helped develop and conduct the one-week FHWA course on seismic design of bridges. He is a member of the Task Force for Highway Structure Seismic Design Damage Investigations of the Earthquake Engineering Research Institute, Committee on Natural Disasters Investigations of the National Research Council, Committee on Concrete Bridges of the Transportation Research Board, and of ASCE.

Dr. Imbsen has been a pioneer in developing, implementing, teaching and applying seismic design principles to bridges since the San Fernando earthquake in 1971. He was a co-recipient of AASHTO's Dr. L.I. Hewes Award for the development of the first comprehensive seismic design specifications, which remained in effect for fifteen years. In addition, Dr. Imbsen has participated in the development of the current AASHTO Division IA and is currently completing the LRFD Guideline Specifications for the Seismic Design of Bridges.