This is the seventh and last in a series of progress reports describing the current results of our reconnaissance geochemical survey of the State of Missouri. The survey was initiated on July 1, 1969, and consists of comprehensive field studies in four research areas-rocks, waters, soils and plants. It was undertaken to provide both a geochemical setting for epidemiological studies by personnel of the Environmental Health Surveillance Center and also a test of the feasibility of broad-scale geochemical surveys in large, geologically diverse regions.