In this chapter, we consider the recent challenges to the psychosocial approach taken in this book. The assumption that the quality of mentalizing is related to the quality of early object relations is a common thread throughout the volume. We argue that many of the known consequences of sensitive as opposed to neglecting and maltreating early environments might be understood as having an impact on the child's capacity to mentalize. However, such assumptions concerning the influence of the child's family environment have recently been challenged by evidence from behavior genetics. Findings from studies of twins and from children adopted early in life are used to claim that past work has exaggerated the influence of parenting on child development. If substantiated, these critiques would remove the logical foundation of most psychodynamic or psychoanalytic approaches, rendering the present proposals, among others, untenable.