Ali H. Nayfeh received his BS in engineering science and his MS and PhD in aeronautics and astronautics from Stanford University. He holds honorary doctorates from Marine Technical University, Russia, Technical University of Munich, Germany, and Politechnika Szczecinska, Poland. He is currently University Distinguished Professor of Engineering at Virginia Tech. He is the Editor of the Wiley Series in Nonlinear Science and Editor in Chief of Nonlinear Dynamics and the Journal of Vibration and Control. Dean T. Mook received his PhD degree in engineering mechanics from the University of Michigan. He is presently Professor at Virginia Polytechnic Institute and State University.