In the past decade, attachment theory has undergone an intense expansion of both its original scientific foundations as well as its applications to clinical work. Bowlby’s original description occurred during a period of behaviorism and then an emphasis on secure base behaviors gave way to dominance of cognitive perspectives. The article then describes another model that draws from both these theories and integrates a psychopathological component of attachment using a developmental and information processing perspective. The discussion leads to the role of trauma and the inherent omission from the Diagnostic and Statistical Manual of Mental Disorders (DSM-V, 2013) criteria for reactive attachment disorder (RAD) even though empirical work has documented the significant and negative impact this has on the development of RAD. The shift moves from the pathology within the individual child to the caregiver’s inability to mentalize or provide a safe environment; the latter constitutes as a type of ‘trauma’ and has been shown to have neurological effects responsible for secure attachment in the child.