From her start as one of the youngest activists in US history, Pauline Newman helped shape the International Ladies' Garment Workers' Union (ILGWU) into a dominant force in industrial America. Cathryn J. Prince tells the story of a self-educated Jewish immigrant who dedicated herself to a legion of causes and lifelong battles against sexism and classism. Prince follows Newman's life from a youth split between Lithuania and New York City sweatshops to her work as an advisor to New Deal–era labor secretary Frances Perkins. Newman's long hours at the Triangle Shirtwaist Factory informed her entrée into labor activism. In the following years, she tirelessly advocated for workers, ran for New York Secretary of State as a socialist, and became the first woman to serve as the ILGWU general organizer. Her interest in the health of workers led to service on the Joint Board of Sanitary Control and a decades-long term as education director of the ILGWU health center. Membership in Eleanor Roosevelt's circle opened doors to government positions and advisory roles that continued into the postwar era. Prince also weaves in the details of Newman's fifty-year relationship with a woman, her struggles with her sexual identity, and her final years. Engaging and panoramic, For the Love of Labor is the first major biography of an important figure in labor and women's history.