The National Geologic Map Database (NGMDB) is the primary source for geologic map and related geoscience information of the United States. It is a Congressionally-mandated function under the Geologic Mapping Act and has been a strong example of State-Federal cooperation since its inception in 1995. The Act stipulates that the USGS (represented by the National Cooperative Geologic Mapping Program) and the Association of American State Geologists (AASG) will create and maintain the National Geologic Map Database as a National Archive of spatially referenced geoscience data including geology, geochemistry, geophysics, paleontology, and geochronology. The Act further stipulates that all new information contributed to the NGMDB should adhere to technical and science standards developed as needed under the guidance of the NGMDB project.