Geotechnical Engineering for Transportation Projects contains 223 papers, presenting the geotechnical and geological aspects of design, analysis, and construction of transportation projects. This two-volume proceedings includes bridges, tunnels and underground structures, rail and highway corridors, and airports and harbors. Highlighted within each presented paper are state-of-the-art practices, as well as recent advancements and emerging technologies in geotechnical engineering. Case histories addressing geosynthetic applications, retaining structures, deep soil mixing, embankment and slope stability, and the use of recycled materials as applied to transportation projects were also presented. The Geo-Institute's Geo-Trans 2004 Conference was held on July 27-31, 2004, in Los Angeles, California.