Military service and deployments put women at risk for adverse mental health outcomes. This retrospective, cross-sectional study examined the pre-deployment, deployment, and post-deployment risk factors and protective processes that may influence post-deployment biopsychosocial and mental health outcomes among Army National Guard (ARNG) women who deployed in support of the Global War on Terrorism (GWOT) between 2003 and 2008. A disproportionate stratified random sample of ARNG women who were members of the District of Columbia (DC), Maryland (MD), and Virginia (VA) National Guard during their GWOT deployments was selected. ARNG women were stratified by state and women in senior ranks (i.e., Sergeant First Class/E-7 and above) were all included in study. The remainder of the ARNG women (Staff Sergeant/E-6 and below) were random sampled. During January and February 2009, 420 questionnaire packets were mailed in two waves using a modified Tailored Design Method (TDM) (Dillman, 2007). Fifty-nine invalid addresses and one duplicate listing were identified. From the remaining 360 questionnaires, 132 were completed and returned, yielding a response rate of 37%. Of the 132 returned questionnaires, 34 ARNG women were not eligible for the study because they did not deploy in support of the GWOT. Therefore, 98 cases were eligible to be included in the analyses. Findings indicated that deployment and post-deployment stressors were positively related to posttraumatic stress symptoms. More pre-deployment stressor experiences and lower levels of post-deployment stressors were associated with resilience. Resilience fully mediated the relationship between post-deployment stressors and posttraumatic stress symptoms, as post-deployment stressors were no longer significantly associated with posttraumatic stress once resilience was included in the model. Consistent with resilience theory, findings further suggest that proximal risk and protective factors are more strongly associated with posttraumatic stress than distal risk factors. As a mediator, resilience may “interrupt” the effect of post-deployment stressors on posttraumatic stress symptoms. Proximal stressors may affect the severity of posttraumatic stress reactions during post-deployment, but resilient qualities have the potential to mitigate risk. Resilience may be a promising assessment and treatment outcome during post-deployment interventions to identify ARNG women who may be at risk for negative post-deployment outcomes.