Citizen Teacher is the first book-length biography of Margaret Haley (1861-1939), the founder of the first American teachers' union, and a dynamic leader, civic activist, and school reformer. The daughter of Irish immigrants, this Chicago elementary school teacher exploded onto the national stage in 1900, leading women teachers into a national battle to secure resources for public schools and enhance teachers' professional stature. This book centers on Haley's political vision, activities as a public school activist, and her life as a charismatic leader. In the more than forty years of her political life, Haley was constantly in the news, butting heads with captains of industry, challenging autocracy in urban bureaucracy and school buildings alike, arguing legal doctrine and tax reform in state courts, and urging her constituents into action. An extraordinary figure in American history, Haley's contemporaries praised her as one of the nation's great orators and called her the Joan of Arc of the classroom teacher movement. Haley's belief that well-funded, well-respected teachers were the key to the development of a positive civic community remains a central tenet in American education. Her guiding vision of the democratic role of the public school and the responsibility of teachers as activist citizens is relevant and inspirational for educators today.