The U.S. Geological Survey has responsibility in the U.S. Department of the Interior to assess the nation's energy and mineral resources. The evaluation of reserves and resources of a commodity such as lithium should be a continuing process in the light of advancing technology and ever-growing knowledge of its geologic occurrence and geochemical behavior. Although reserves of lithium vary with market demand because of the investment required to find, develop, and appraise an ore body, total resources are a function of the geologic occurrence and geochemical behavior of lithium. By studying known deposits and publishing data on their origin and occurrence, the U.S. Geological Survey can aid in the discovery of new deposits and improve the resource base. Resource data are used both by the government and the private sector. Government funding for research on energy-related technologies such as electric vehicle batteries and fusion power requires assurance that there will be enough lithium available in time for commercialization. Questions of availability for all mineral commodities must be answered by the U.S. Geological Survey so that intelligent decisions can be made. ?? 1978.