The Observation of Infants in a Set Situation (1941). Primitive Emotional Development (1945). Hate in the Countertransference (1947). Mind and its Relation to the Psyche-Soma (1949). Transitional Objects and Transitional Phenomena (1951; 1971). Metapsychological and Clinical Aspects of Regression Within the Psychoanalytical Set-up (1954). The Theory of the Parent-infant Relationship (1960). The Development of the Capacity for Concern (1963). Communicating and Not Communicating Leading to a Study of Certain Opposites (1963). Fear of Breakdown (1963). A Clinical Study of the Effect of a Failure of the Average: Expectable Environment on a Child’s Mental Functioning (1965). Playing: A Theoretical Statement (1968). The Use of an Object and Relating Through Identifications (1968). Creativity and its Origins (1971).