The United States is known as a country that has been highly antagonistic to Socialism of any form. Socialists in the United States have tended to be political outsiders, mounting criticisms of the government without serving in elected office themselves. However, from around 1900 to 1920, Socialist politicians in the United States were prominent and active at the municipal level, holding office as government insiders. Socialist mayors in over two hundred small cities across the United States brought meaningful improvements in the quality of life for people in their communities, playing an important role in this period’s municipal reform movement. Despite the limitations of being associated with a minority party—particularly a party that divided over whether to pursue elected office in the United States—these mayors pushed for reforms, challenged the status quo, and held their own in demonstrating the ability to govern. Socialist Mayors in the United States is the first comprehensive study of nationwide Socialist activity at the municipal level during the Progressive Era. It is a unique study of the Socialist mayors in this period: their election, how they approached their job, and what they accomplished. Berman offers a fresh look at the nature of the Socialist Party by focusing on its municipal program, interaction with non-Socialist municipal reformers, local political operations, and the tensions within the party as it delved into political action on this level. Socialist Mayors in the United States is an illumination of seldom-explored political and governmental characteristics of medium and small towns, often very small towns, where Socialists enjoyed most of their successes.