Water-resources activities of the U.S. Geological Survey in Missouri consist of collecting hydrologic data and making interpretive studies. Hydrologic studies in Missouri are made through three basic types of projects:(1) hydrologic data-collection programs, (2) local or area! hydrologic investigations, and (3) statewide or regional studies. These -projects are funded through joint-funding agreements with State and local agencies, transfer of funds from other Federal agencies, and direct Federal funds. These data and the results of the investigations are published or released by either the U.S. Geological Survey or by cooperating agencies. This report describes the hydrologic data-collection programs and local or area! hydrologic investigations in Missouri for fiscal year 1985 and provides a list of selected Water-resources references for Missouri.