Although strikingly soft-spoken, Gittings changed the lives of people in the gay and lesbian community. She came out in the conservative era of the 1950s, and formed a branch of the first national organization for lesbians in New York. Her lobbying efforts resulted in changing the classification of homosexuality as a mental illness by the American Psychiatric Association, and one of her protest signs, which she carried in a 1965 White House protest, now hangs in the Smithsonian.