In the summer of 1969, a federal district court in Denver, Colorado, heard arguments in one of the nation’s first explicitly environmental cases, in which the Defenders of Florissant, Inc. opposed real estate interests intent on developing lands containing an extraordinary set of ancient fossils. This book, the first account of the fight to preserve the Florissant fossil beds, tells a story of environmental activism that remains little known more than forty years after the coalition’s victory. The principal author, Estella Leopold, was a major participant in the process.