The Digital Mapping Techniques '09 (DMT'09) workshop was attended by 90 technical experts from 42 agencies, universities, and private companies, including representatives from 24 State geological surveys (see Appendix A). This workshop, hosted by the West Virginia Geological and Economic Survey, May 10-13, 2009, on the West Virginia University campus in Morgantown, West Virginia, was similar in nature to the previous 12 meetings (see Appendix B). The meeting was coordinated by the National Geologic Map Database project.