Austrian psychoanalyst who was a major influence in child psychology and psychiatry, devising techniques of analysis that gave insight into the depths of a child's mind.
Klein began her training in child psychoanalysis in Budapest with Sándor Ferenczi (1873–1933), a close associate of Freud, and later studied in Berlin with Karl Abraham (1877–1925). She developed a method of analysis using children's free play with small toys and their spontaneous communication, which she believed provided an insight into their desires and anxieties, their relationships with parents, and their fantasies and psychological defences during the early years of life. Her methods initially provoked much criticism: although Freud's work on adults showed that many fantasies and anxieties were rooted in childhood, Klein suggested that they were already established early in infancy and provided evidence of superego and an Oedipus complex in a two-and-a-half year old child. This, and the idea that sadism and aggression are present in infants, were found shocking but her theories and methods of therapy later gained wide acceptance.
In 1926 Klein moved to England to work at the British Psychoanalytical Society and spent most of her working life in London. In The Psychoanalysis of Children (1932), she presented her techniques and observations of anxiety situations in infancy and their effect on normal growth and the development of emotional disorders. Klein believed that a child could be protected from later mental disorders by psychoanalysis. After 1934 she worked with adults to extend her studies of child anxiety situations and made valuable contributions to the psychopathology of depressive and schizoid-paranoid illnesses that have their origins in childhood.