Exposure to traumatic events (that include but are not limited to experiencing physical or sexual assault, accidents, or natural disasters or witnessing such events) can lead to psychological and physiological difficulties. Between 21 million and 36 million Americans (7 to 12% of the general population) have suffered from PTSD, and rates of exposure to traumatic events are notably higher. Survivors of trauma may find it difficult to function in society or perform routine daily activities. Given the increased chance of negative health outcomes in trauma-related disorders, there is a great deal of interest in this disorder and its impact on the immune system. Although the exact biological mechanisms that occur following traumatic events have still to be elucidated, there is some evidence of increased expression of nonspecific pro-inflammatory Interleukin-1β and Interleukin-6 immune responses, as well as increased expression of the stress hormone cortisol. The primary objective of the presently proposed study is to examine whether the levels of physiological outcome variables (e.g., immune responses, cortisol, blood pressure) improve in response to psychotherapy. Participants will be 20 volunteers from the NSU Trauma Resolution and Integration Program (TRIP). While concurrently receiving treatment within the TRIP clinic, each volunteer will have their physiological activity, immune activity, psychological stress, depression, dissociation, and PTSD symptoms measured each month, for six months. The results of the proposed project may provide increased understanding of the physiological variables that respond to successful trauma treatment, relationships between physiological and psychological variables associated with trauma exposure, and relationships between the physiological variables and chronic pain and/or chronic health conditions. Improved understanding of health outcomes associated with psychotherapy would provide insight into the mechanisms that may help to prevent premature illness among individuals experiencing posttraumatic stress reactions.