Dr. Delahanty's research largely focuses on examining psychophysiological responses to stress and whether differential responses to stress are associated with persistent negative outcomes. He and his students are currently examining different hormonal and psychological reactions to traumatic stress in a variety of populations to identify variables that are predictive of the subsequent development of posttraumatic stress disorder (PTSD). Based on these findings, we develop novel early clinical and pharmacological interventions to prevent the development of PTSD and comorbid disorders. We are also interested in the extent to which PTSD and comorbid disorders interfere with health behaviors and conduct interventions in chronic PTSD patients in order to determine whether symptom alleviation results in greater medication adherence, less substance use, and greater quality of life. Finally, we have several laboratory-based studies in which we examine reactions (e.g. cardiovascular reactivity) to more acute stressors in order to inform our understanding of mechanisms through which stress impacts health.