'This is a book worth savoring, not just reading. The authors' breadth is truly staggering, traversing terrain from philosophy of mind, to developmental research on children's capacity to represent their own and others' mental states, to research on severe personality disorders, to clinical observations of infants, children and adults - all within a framework grounded in attachment theory. It is one of the first truly convincing efforts to show how the body of attachment research can actually influence the way we practice with many of our patients.' - Drew Westen.