In this classic study, Henri Parens and Leon J. Saul provide a comprehensive review of Freud s writings on the subject of dependence, drawing attention to the fact that Freud said much more about dependence than is generally recognized. The authors proceed to supplement the theory of dependence from their own perspective, drawing on the formulations of Rene Spitz and the findings of ethologists (especially in imprinting and primary socialization) in order to shed further light on the singularity of early human development. They postulate the libidinization of dependence and trace the effects of this on psychic development, and also consider the dependence continuum in dynamic and economic terms ( inner sustainment ), which reflects the equilibrium between dependency and self-reliance. Utilizing Anna Freud s developmental lines and Margaret Mahler s sub phases of separation and individuation, they trace the epigenesis of dependence and provide illuminating clinical examples."