Site and Geomaterial Characterization addresses issues ranging from the micro-characterization of processes to the in situ evaluation of engineering properties of soils. This Geotechnical Special Publication contains over 40 technical papers that were presented at the GeoShanghai Conference held in Shanghai, China from June 6-8, 2006. This book is divided into four main sections, with all of the papers addressing one of the greatest challenges in geotechnical engineering research and practice: the evaluation of geomaterial properties with minimal to no disturbance states. The first section includes the general theme paper by James K. Mitchell, University Distinguished Professor, Emeritus, Virginia Polytechnic Institute and State University, who focuses on the study of physico-chemical behavior of soils, soil improvement and geomaterial characterization. The second section is completely devoted to recognizing the services of Dr. Mehmet T. Tumay, Georgia Gulf Distinguished Professor Emeritus in the Department of Civil and Environmental Engineering at Louisiana State University, for his immense contribution to research and practice in geotechnical engineering. The third section covers non-destructive evaluation and geophysical testing to address soil characterization problems relevant to foundation exploration, geoenvironmental evaluation and earthquake related topics. Finally, the fourth section contains other in situ testing methods that deal with the analysis of field data and interpretation of soil properties, as well as simulation of in situ testing using numerical methods.