"Maps for America" was originally published in 1979 as a Centennial Volume commemorating the Geological Survey's hundred years of service (1879-1979) in the earth sciences. It was an eminently fitting Centennial Year publication, for, since its establishment, the Geological Survey has continuously carried on an extensive program of mapping to provide knowledge of the topography, geology, hydrology, and natural resources of our Nation. This volume contains an organized presentation of information about the maps produced by the Geological Survey and other American organizations, public and private. Such maps are important tools for those in government and in private endeavors who are working to assure the wisest choices in managing the Nation's resources. They are particularly supportive of the Department of the Interior's role as the Nation's principal conservation agency. The second edition of "Maps for America" is intended primarily to replenish the dwindling supply of copies of the book, but it also contains a number of changes to correct or update the text and to provide more suitable illustrations in certain instances.