We examined the effect of family life, work, and war-related stressors on posttraumatic stress disorder (PTSD) symptoms, depression symptoms, perceived physical health, and perceived functioning in a large sample of 796 randomly selected Air Force men and women who were deployed during the period of October 7, 2001 to September 2004. As predicted by conservation of resources (COR) theory, we found that these combined sources of stress directly affected PTSD and depression symptoms and that resource loss, more than resource gain, mediated these effects. We further found that greater PTSD and depression symptoms were related to diminished physical health and poorer functioning. Contrary to what COR theory might predict, resource losses did not have a greater direct effect on perceived health and functioning than resource gain. However, because stressors had so much greater effect on resource loss than on gain, and resource loss had so much more direct effect on PTSD and depression symptoms than resource gains, it is still the stronger mediator of the effects of stressors on perceived health and functioning than resource gain. Critical for military policy, our results highlight the greater importance of limiting resource loss cycles than promoting gain cycles, even if each has a role in supporting or undermining well-being, psychosocial and work functioning, and deployment readiness. (PsycINFO Database Record (c) 2013 APA, all rights reserved)