Systematic underground-water investigations have been in progress in the State of Utah since 1935 by the Federal Geological Survey in cooperation with the state engineer. The general plan and outline of these investigations, together with a summary of results accomplished to June 30, 1940, are given in the Twentieth, Twenty-first, and Twenty-second biennial reports of the state engineer to the governor of Utah. The investigations include two important phases: (1) A determination of the fluctuations of water levels and artesian pressures in most of the underground-water areas in the state, based on periodic measurements with steel tapes and on charts of automatic water-state recorders and pressure recorders, and (2) detailed investigations of individual underground-water areas to determine the source, movement, disposal, quantity, and quality of underground water, and to show the relation of present development to the maximum economic development of those areas. The aim of the investigation is to determine and make available factual data as to underground-water conditions in the different areas of the state so that they may serve to guide the state engineer in an equitable adjudication of underground-water resources.