U.S. soldiers' appraisal and experience of the Kosovo peacekeeping mission is described. Using a prospective design, we evaluated the prevalence, severity, and predictors of several mental health outcomes at redeployment. We found that peacekeepers frequently were exposed to potentially traumatizing and other stressful events while in Kosovo, but on average, their appraisal of those events was moderate. Postdeployment psychopathology was also low--soldiers endorsed more severe mental health difficulties at predeployment, which suggests anticipatory negative affect. After controlling for the impact of predeployment stressors, we examined the contribution of potentially traumatizing events, general overseas military duty stressors, negative aspects of peacekeeping roles, and generic positive military experiences, including morale, to explain variance in four outcomes: post-traumatic stress disorder, depression, hostility and aggression problems, and problems with alcohol abuse. Findings indicate that hostility and drinking may be more chronic problems that emerge during stressful times, whereas depression and post-traumatic stress disorder symptoms may be more apt to fluctuate and are associated with potentially traumatizing experiences during peacekeeping. The implications and limitations of the study are discussed.