Reactive Attachment Disorder is a diagnosis that develops after a child has had sequential and repetitive early childhood trauma the first two to three years of life, and/or pervasive neglect, or long term institutional care that we see coming out of other countries in children that are being adopted here. It can only develop up to age five. After age five if it has not developed it will not develop, however, it is a very foundational disorder, and so intervention and treatment need to be focused at those very early traumatic experiences, and not the more superficial kind of behavioral things that parents are seeing in their families. It's rare in the population in general. In a foster care population or institutionalized children population it's estimated about 80% of kids who have had early childhood maltreatment have insecure attachments.