Attachment and Health
John Bowlby and Mary Ainsworth developed attachment theory in the 1960s while investigating the effects of maternal separation on infant development. The development of the Strange Situation task in 1965 by Ainsworth and Wittig allowed researchers to systematically investigate the attachment system operating between children and their parents. The Strange Situation involves separating infant-parent dyads and observing infant behaviours upon reunion. Infant behaviour tended to follow patterns, leading to the development of three attachment categories: Secure, Anxious-Avoidant, and Anxious-Resistant. In 1990, Ainsworth added a new category, championed by Mary Main, called Disorganized/Disoriented attachment, characterized by its less reliable pattern of behaviour.
Gordon Neufeld
Gordon Neufeld (1946) is a developmental psychologist and author of the book "Hold on to Your Kids: Why Parents Need to Matter More Than Peers" (co-authored with Canadian physician Gabor Maté) that has been translated into 10 languages.
The Neufeld approach (his attachment-based developmental model) is based on the attachment theory formulated by John Bowlby.
He developed a theory of attachment that includes six stages in the development of the capacity for relationship, the construct of polarization that explains both shyness and defensive detachment. His model of attachment is universal in both its application (adults as well as children) and implementation (school as well as home).