Children raised in institutions frequently suffer from a variety of behavioral, emotional, and neuropsychological sequelae, including deficits in attention, executive functions, disorders of attachment, and in some cases a syndrome that mimics autism. The extent and severity of these disorders appear to be mediated, in part, by the age at which the child entered and, in some cases, left the institution. Here we review the neurobiological literature on early institutionalization that may account for the psychological and neurological sequelae discussed in other chapters in this volume.