Born Joanna Sullivan in 1866 (though referred to as Anne or Annie), she became the tutor of six-year-old Helen Keller in 1887, and her rapid progress in teaching her blind, deaf and mute pupil earned the pair considerable repute. Accompanying Keller through her education, she demonstrated great dedication, spelling out her lectures and reading to her for hours a day.

Sullivan herself had been rendered nearly blind by an earlier illness (though surgery had restored some sight) and been, like her charge was then, a pupil of the Perkins Institution for the Blind. This was most likely an important factor in their success.

She experienced a failed marriage to John A. Macy, a Harvard instructor. Accompanying Keller on her lecture circuit, and at home, her exertions taxed her health; complete loss of sight occurred in 1935 and death in 1936.