The experience of traumatic events is a near-universal, albeit unfortunate, part of the human experience. Given how many individuals are exposed to trauma, it is interesting to question why some individuals are resilient in the face of trauma while others go on to develop chronic post-traumatic stress. Throughout the relatively brief history of the psychological study of trauma, a number of themes have consistently emerged. Many of these themes remain essential elements within the current study of traumatic stress disorders, as summarized within this volume, which addresses the current landscape of research and clinical knowledge surrounding traumatic stress disorders. Bringing together a group of experts, the volume is divided into six sections, together summarizing the current state of knowledge about: classification and phenomenology; epidemiology and special populations; contributions from theory; assessment; prevention and early intervention efforts; and treatment of individuals with post-trauma mental health symptoms. Throughout the volume, attention is paid to identifying current controversies in the literature and highlighting directions that hold promise for future work.