Ego psychology represents a dominant paradigm in the study of personality. However, it is a confusing tradition, embracing a number of different schools of thought. One could point to at least two distinct European varieties, linked with the names of Jung and Anna Freud, and as many as three North American branches, associated with the following figures: Hartmann, Rapaport, and Nunberg; Allport, Murray, Ausubel, and White; and Sullivan and Erikson.