Everyone was brave from the moment she walked into the room,” Cleveland politician and reformer Newton Baker once said of the fearless and charismatic woman who led the National Consumers’ League for 24 years. Working outside the courtroom, Kelley mobilized the popular support and legal talent that revolutionized American labor law between 1890 and 1930. In doing so, she improved the lives of millions of workers.

Florence Kelley viewed the law as a tool to achieve social justice. She showed other lawyers how to gather persuasive evidence and use it to defend social legislation before hostile courts. Her tactics were so effective that Felix Frankfurter asserted that she “had probably the largest single share in shaping the social history of the United States during the first 30 years of this century.”