She implemented systems of inmate classification, decentralized housing, and other reforms that were later adopted throughout the Federal Bureau of Prisons.[2] In 1914, Harris was offered a position as a prison superintendent by Katharine Bement Davis, who was then Commissioner of Corrections in New York City.Harris took a leave of absence from the reformatory later in the year to assist Martha P. Falconer with the U.S. Department of War's Commission on Training Camp Activities.[4] As superintendent of the Federal Industrial Institution for Women, Harris promoted vocational training and provided areas for physical activity and farming.Harris believed in indeterminate sentencing, fostering self-respect, and that women usually committed crimes out of an "economic or psychological dependency, especially on men".[5] Following the formation of the Federal Bureau of Prisons (BOP) in 1930, Harris resisted bureaucratic control, maintaining independence for the institution.[6] She disagreed with BOP Directors Sanford Bates and James V. Bennett on the need for a maximum security prison for women.[5] She used women's networks, the prison's advisory board, and her relationship with Eleanor Roosevelt to protect the character of the institution.