Dr. Porges is a developmental psychologist and neuroscientist who has been studying the relation between the nervous system and behavior for over 30 years. His interest in at-risk infants and children began early in his career. His Polyvagal Theory, published in the journal Psychophysiology in 1995, led to the discovery of an integrated neural system that regulates social engagement behaviors. A description of this Social Engagement System was recently published in the journal Psychoneuroendocrinology. The Polyvagal Theory led to the development of an intervention for children with severe problems in social interaction and communication. Initial research with the intervention has yielded beneficial results for the majority of children tested. Research on the intervention continues, with the hope of one day being able to provide the intervention to all children who might benefit.