Post-traumatic stress disorder (PTSD) is a disabling psychiatric condition characterized by a persistent maladaptive reaction resulting from exposure to severe psychological stress. It has been revealed that individuals with PTSD, in addition to adverse mental health symptoms, also possess higher prevalence rates for physical comorbidities such as hypertension, obesity, diabetes, and metabolic syndrome. Taken together, these PTSD-induced comorbidities result in a significant increase in the likelihood of developing cardiovascular disease (CVD) when compared to individuals without PTSD. Peripheral vascular dysfunction, or the inability of the blood vessels to adequately respond to specific stimuli, is a factor closely related to CVD. Therefore, this study will focus on a younger population with PTSD in an attempt to ascertain the presence of peripheral vascular dysfunction and the magnitude to which two potential primary contributors (autonomic dysfunction, oxidative stress) are involved in this dysfunction.