Stephen W. Porges, PhD, has been an academic for more than 50 years and currently holds positions as a distinguished university scientist at Indiana University, professor of psychiatry at the University of North Carolina and the University of Florida College of Medicine in Jacksonville, and professor emeritus at the University of Illinois at Chicago and the University of Maryland. He has published more than 400 peer-reviewed scientific papers that have been cited in more than 58,000 peer-reviewed papers, and he holds several patents related to technologies involved in monitoring and regulating autonomic state. Stephen also served as president of the Society for Psychophysiological Research and the Federation of Associations in Behavioral & Brain Sciences and is a former recipient of a National Institute of Mental Health Research Scientist Development Award. He is the originator of the Polyvagal Theory, which emphasizes the importance of physiological state in the expression of behavioral, mental, and health problems, and he is the creator of a music-based intervention, the Safe and Sound Protocol, which is the focus of this book. In collaboration with Anthony Gorry, he cocreated an acoustic intervention, the Rest and Restore Protocol, engineered to support homeostatic functions, and with Karen Onderko, Deb Dana, and Randall Redfield, he founded the Polyvagal Institute.