I have attempted to elaborate and integrate the contributions of some of the major observers and theorists of early development, and to build a bridge between the structuralist point of view and the object relations perspective of Mahler. Observations of infants between the ages of 2–18 months, approximately, and observations from the therapy of adults with primitive personality disorders have been used to evaluate, criticize, and refine Mahler's schema from symbiosis to rapprochement. The major emphasis is on the development of the symbiotic bond, which is described as biphasic. The first, or unconditional phase, before unpleasure is specifically represented, corresponds to Freud's 1930 formulation of the ego that includes everything. The second, or territorial phase, parallels the development of capacity to represent the unknown and to project unpleasure, around 8 months of age. Considerable attention has also been paid to early perceptual-cognitive-affective motor development and to the process of early internalization and structure-building.