Proceedings of the 2014 Geo-Congress, held in Atlanta, Georgia, February 23-26, 2014. Sponsored by the Geo-Institute of ASCE. GSP 234, Geo-Congress 2014 Technical Papers: Geo-Characterization and Modeling for Sustainability, contains 413 peer-reviewed technical papers and case studies on efficient and sustainable practices in the design and construction of crucial geotechnical infrastructure. GSP 235, Geo-Congress 2014 Keynote Lectures: Geo-Characterization and Modeling for Sustainability, contains eight peer-reviewed keynote papers on cutting edge aspects of sustainability-related geotechnical issues. These papers will be of interest to practitioners, researchers, students, and policymakers working to address sustainability in the area of geotechnical and geoenvironmental engineering.