Margaret Schönberger Mahler (May 10, 1897 – October 2, 1985) was a Hungarian physician, who later became interested in psychiatry. She was a central figure on the world stage of psychoanalysis. Her main interest was in normal childhood development, but she spent much of her time with children in psychiatric treatment and how they arrive at the "self". Mahler developed the separation–individuation theory of child development.