Two studies examined the contributing factors for panic symptoms following trauma. In Study 1, survivors of sexual and nonsexual assaults (N=105) were assessed at 2 weeks postcrime. Prior trauma, psychiatric history, crime characteristics, and peritraumatic dissociation were assessed. Posttraumatic panic was modestly predicted by childhood sexual abuse (CSA) experiences, a history of Anxiety and Depression, and peritraumatic dissociation. Childhood physical abuse (CPA), Adult Victimization, crime variables, and a prior history of Substance Use disorders and posttraumatic stress disorder (PTSD) were not implicated. In Study 2, the role of peritraumatic panic in predicting later arousal was also examined in a similar sample who were assessed within 6 weeks of their trauma (N=93). Presence of significant arousal during trauma predicted frequency of posttrauma panic attacks, but not its severity. In contrast to Study 1, prior history of PTSD, perception of life threat, and the index trauma being a sexual assault all predicted posttrauma panic, whereas prior trauma exposure and depression did not. These findings are discussed in terms of cognitive and arousal factors that may influence posttrauma panic.