Margaret Mahler was a 20th century psychiatrist who studied children's development and developed the theories of individuation and separation. 

Professional Life

Margaret Mahler was born in Hungary on May 10, 1897. She became interested in psychoanalysis as a teen when she met Sandor Ferenczi. She studied medicine at the University of Budapest beginning in 1917, before transferring to the University of Jena in Germany to study pediatrics. She graduated in 1922 and settled in Vienna, Austria. She began training in psychoanalysis in 1926. After several years of working with children, Mahler was certified as an analyst in 1933.

She married Paul Mahler in 1936, and the couple fled Austria as the Nazis rose to power, settling in Britain before moving to New York in 1938. She began a private practice and worked with experts such as Dr. Benjamin Spock. Mahler taught child therapy and was a member of the New York Psychoanalytic Society and the Institute of Human Development. She also became heavily involved in research directed toward pediatric mental health. She taught at Columbia University between 1941 and 1955, and she served as a clinical professor of psychiatry at the Albert Einstein College of Medicine until 1974.

Mahler spent most of her career working with psychologically impaired children. She was among the first psychologists to specialize in the treatment of psychotic children. Her work in this area led to the book The Psychological Birth of the Human Infant: Symbiosis and Individuation. In addition, she co-founded the Masters Children’s Centre in New York with her colleague Manuel Furer. It was from here that Mahler created and taught the Tripartite Treatment Model, a therapeutic approach involving both the child and mother.

Mahler received several awards for her work throughout her career, including Barnard College's highest honor, the Barnard Medal of Distinction, in 1980. Mahler passed away in 1985 in New York City.  

Contribution to Psychology

Mahler’s most significant contribution to the field of psychology was her theory on separation and individuation. Mahler believed that children exist in a symbiotic phase until they reach about six months of age. During this time they are unaware of their surroundings and others and only are cognizant of themselves as one with their mothers. They do not see beyond that relationship. After about the age of six months, the separation-individuation phase commences and the child begins to distinguish him- or herself from the mother, thus developing an individual identity and ego. It is during this phase that the child also begins to develop cognitive skills and master the ability to communicate with others. For Mahler, this “psychological birth” proceeds according to a predictable pattern:

  • The normal autistic phase occurs during the first weeks of life and shows little social engagement. However, Mahler abandoned this phase later in her career. 
  • The normal symbiotic phase lasts through the first six months of life, and occurs when the child gains awareness of caregivers but has no sense of individuality. 
  • The separation-individuation phase takes place at about four or five months, as the child begins to develop a sense of self, separate from the mother. This is further broken down into subphases that proceed in a predictable order:
    • Differentiation, or “hatching,” occurs when the child first gains awareness that he or she is separate from the mother.
    • Practicing occurs as the child becomes a toddler, gaining motor skills that enable the child to explore the world independently from his or her caregivers. 
    • Rapprochement marks a “backing off” from separation, as the child becomes anxious about separating from his or her mother and tries to regain closeness. This can lead to separation anxiety and abandonment fears. As a child develops language skills, this phase winds down.

Mahler proposed that early in development the child does not have a concept of object constancy for the mother, which means when the mother disappears, she ceases to exist. This concept is similar to Jean Piaget's theory of object permanence.

As a child matures, perception of his or her mother begins to evolve and the child internalizes the image of her. Children who hold positive internal images of their mothers continue to feel support throughout adulthood, while those who do not may struggle with insecurities relating from their childhood perceptions. Mahler argued that disruptions in the normal developmental trajectory could lead to maladaptive behavior, including child psychosis.


  1. Bird, D. (1985, Oct 03). Dr, Margaret S. Mahler, 88; Studied Child Development. New York Times. Retrieved from
  2. Mazet, Philippe. (2005). Margaret Mahler-Schonberger. International Dictionary of Psychoanalysis. Biography In Context. Retrieved from