This book explores Eleanor Roosevelt’s involvement in the global campaign for nuclear disarmament. Based on an extensive multi-archival research, it assesses her overall contribution to the global anti-nuclear campaign of the early cold war and shows how she constantly tried to raise awareness of the real hazards of nuclear testing. She strove to educate the general public about the implications of the nuclear arms race and, in doing so, she became for many a trustworthy anti-nuclear leader and a reliable voice of conscience.