Labor historian James J. Lorence presents the first comprehensive biography of progressive labor organizer, peace worker, and economist Clinton Jencks (1918 - 2005). A key figure in the radical International Union of Mine, Mill, and Smelter Workers (IUMMSW) Local 890 in Grant County, New Mexico, Jencks was involved in organizing not only the mine workers but also their wives in the 1951 strike against the Empire Zinc Company. He was active in the production of the 1954 landmark labor film dramatizing the Empire Zinc strike, Salt of the Earth , which was heavily suppressed during the McCarthy era and led to Jencks's persecution by the federal government.