[Excerpt from author] Of two major types of trauma - interpersonal and non-interpersonal - the most common, for most people, is interpersonal trauma. This trauma can come from being the recipient of actual violence from one person upon another, e.g., rape or beating, observing violent acts of one person upon another, e.g., fights or stabbings, or being demeaned and berated by someone of influence in one's life. All of these actions can be a threat or perceived threat to one's safety and well being. The target person's physiology, behaviors, and thoughts can change so that the person may suffer from a variety of symptoms - some short- term, some chronic, or none at all. Why some persons suffer sequelae and others do not remains an unanswered question even though some hints are being identified.