The National Environmental Methods Index (NEMI) Is a searchable database of official methods for environmentally significant analytes sponsored by the EPA and the USGS. Methods in the database are either from governmental agencies (EPA, USGS, DOE or NOAA) or from other organizations that develop reliable analytical methods (ASTM, AOAC). Although some of the later methods are proprietary, those from the governmental agencies are freely available for download as pdf documments. The NEMI software is launched from the homepage and methods for analytes can be searched and listed by organization, method number, testing method, and cost or browsed. If you don't have the exact analyte name, there is a separate search page for locating the exact analyte in the database. This is a valuable website for advanced instrumental analysis courses, and capstone/senior projects in chemistry, biology, environmental chemistry, and geology/geochemistry.