Conservation was the first nationwide political movement in American history to grapple with environmental problems like waste, pollution, resource exhaustion, and sustainability. At its height, the conservation movement was a critical aspect of the broader reforms undertaken in the Progressive Era (1890-1910), as the rapidly industrializing nation struggled to protect human health, natural beauty, and "national efficiency." This highly effective Progressive Era movement was distinct from earlier conservation efforts and later environmentalist reforms. Conservation in the Progressive Era places conservation in historical context, using the words of participants in and opponents to the movement. Together, the documents collected here reveal the various and sometimes conflicting uses of the term "conservation" and the contested nature of the reforms it described. This collection includes classic texts by such well-known figures as Theodore Roosevelt, Gifford Pinchot, and John Muir, as well as texts from lesser-known but equally important voices that are often overlooked in environmental studies: those of rural communities, women, and the working class. These lively selections provoke unexpected questions and ideas about many of the significant environmental issues facing us today.