Born in Rochester, New York in February 1889, Sadie P. Delaney attended Poughkeepsie High School, the College of the City of New York and received her professional training in the New York Public Library.

Mrs. Delaney was a pioneer in the field of bibliotherapy and organized the Veterans Administration Hospital Library in Tuskegee, Alabama. Before assuming the post of Chief Librarian at the Veterans Hospital in 1923, Mrs. Delaney began her career in librarianship at the 135th Street Branch of the New York Public Library in 1920. There she found that immigrants and troubled children could be helped through bibliotherapy (the therapeutic use of reading materials). Her initial work in bibliotherapy received international attention. Mrs. Delaney also had a special interest in books dealing with black history and literature and wanted to develop a collection with such a focus. She thus came to know Arthur A. Schomburg, the bibliophile and collector. Mrs. Delaney was cited for exceptional work at the 135th Street Branch Library and founded the first black professional women's club in New York City. In 1928 she married Rudicel A. Delaney.

Mrs. Delaney's innovative work at the Veterans Hospital in Tuskegee brought world recognition and acclaim. Bibliotherapy and group therapy for the mentally ill and disabled, special Braille therapy for the blind and other related activities at the hospital library were the primary focus of her life's work. She affiliated with others of the library profession, nationally and internationally. She was a member of the American Library Association and its committee for work with the blind; the International Library Association at Queens Garden, England; the International Hospital Library Guild; the League of Nations Library Committee; the Neuropsychiatric Journal Club at the Veterans Hospital in Tuskegee; and the Mental Hygiene Society of Tuskegee Institute. Mrs. Delaney also affiliated with organizations which addressed broader social concerns. She was a member of the National Council of Colored Women, a charter member of the “Women of Darker Races of America,” a member of the Tuskegee Women's Club, and the founder of the Friendship League of America. She organized the College Chapter of the National Association for the Advancement of Colored People in New York City and served seven and one-half years on the advisory board of the New York City N.A.A.C.P. Mrs. Delaney was elected as the councilor for the Hospital Library Division of the American Library Association and served from 1946 until 1951.

For her pioneering work as a bibliotherapist, humanitarian and leader in professional and social circles, Mrs. Delaney received numerous awards, honors and citations. In 1934 she was selected by the Mitre Chambers, London, England as one of the important women in America and included in the book Principal Women of America. It was also during this period that she organized a special library department for the blind at the Veterans Hospital. In 1938 she was cited by the Carnegie Corporation, Pretoria, South Africa for exceptional work in hospital libraries. She was selected as Woman of the Year by the Iota Phi Lamba Sorority and Zeta Phi Beta Sorority in 1948 and 1949 respectively. In 1950 Mrs. Delaney received the National Urban League Award as Woman of the Year and an Honorary Degree of Doctor of Humanities from Atlanta University. In 1952 she was honored at Howard University by the National Council of Negro Women. Dr. Delaney resided in Tuskegee, Alabama until her death in 1958.