The Gilded Age, 1870s–1890s, was marked by rapid industrialization, unprecedented wealth for a few “robber barons,” and deep social and political inequities hidden beneath a veneer of prosperity. This era’s unchecked corporate power, political corruption, and unsafe working and living conditions aroused widespread discontent. Journalistic exposés by muckrakers spotlighted these injustices, fueling public demand for reform. A broad progressive movement emerged in the 1890s, advocating governmental regulation, democratic reforms, and professionalized approaches to social problems. Jim Kenney examines key players on each side, the shifting values, and the immediate and long-term political consequences of one of the most important transitions in American history.