Combat experiences can have formative effects on a veteran’s beliefs and behaviors that change well-being in unforeseen ways. This dissertation estimates the impacts of (i) service in war environments and (ii) exposure to traumatic events on three well-being aspects—sexually transmitted diseases (STDs), financial problems (such as bankruptcy), and homelessness—in surviving deployed veterans. Estimations use 1994–2016 data from the National Longitudinal Study from Adolescent to Adult Health and Millennium Cohort Study, information theoretic methods relying upon minimal assumptions, and exogenous variation resulting from deployment location assignments. Estimations considering only the broader level location assignment, service in a war environment, do not explain individual changes in well-being; however, estimations with the more refined location assignment reveal links between a deployed veteran’s exposure to traumatic events and increases in STDs, financial problems, and homelessness. Estimated average effects of combat exposure on each well-being aspect are robust to controls for pre-deployment characteristics, time spent deployed and physical harm. Harmful effects of combat exposure on financial problems and homelessness increase with multiple exposures and poorer pre-deployment health. Harmful effects of combat exposure on STDs appear partly due to increases in substance use and the number of sexual partners, a proxy for relationship stability. Results are relevant to discussions regarding resource needs for military readiness and individuals with past traumatic exposure or increased risk for future traumatic exposure.