Since the many broader developmental propositions common to the theories of Piaget, Werner, and psychoanalytic ego psychology are not available in the usual research report, the present paper starts by defining a number of them to provide an outline of the conceptual framework which these three developmental theories share. This framework delineates the limits of the literature survey which follows. Four main lines of investigation are then reviewed, each dealing with questions and hypotheses derived from one or more of the propositions and each suggested by an examination of the literature. These are: studies dealing with innately given behavioral and structural organs and modes of functioning; differentiation-integration and levels of organization; multiple modes and stages of development; and the adaptive process. Following this literature review, a concluding section considers some implications of the biodevelopmental research reported to date for the understanding of child psychopathology.