Participation in Peace Support Operations (PSOs) is one of the most common military duties assigned to present-day Western soldiers. Previous research concerned with the psychological effects of these missions on the individual soldier has focused on issues of mental health and how to ensure military effectiveness. This study takes a different perspective, and examines how PSOs affect the political psychology of the peace soldier, asking: how and to what extent do the sociopolitical psychological orientations of the individual soldier change as a consequence of peace support operations? The study combines theory from clinical, social, and personality psychology to construct a framework for understanding how and why the values and the attitudes toward violence of the soldier may be affected by PSO deployments. It is argued that although combat exposure may cause changes in attitudes and values, these variables will overall remain stable across the deployment. Stability is predicted to be the norm due to the importance of certain attitudes and values to the soldierly identity, and owing to the good person-environment fit that the deployment provides for the soldiers. It is also argued that the individual’s personality traits will predict levels of change and stability. Empirically, two Swedish contingents deployed to northern Afghanistan under the auspices of NATO’s ISAF mission are analyzed. Change and stability are examined by combining statistical analyses of surveys with in-depth interviews carried out at both the pre- and post-deployment stages. As hypothesized, the study finds that both values and attitudes exhibit high levels of stability across the mission. Contrary to expectations the soldiers’ experiences of combat exposure had little to no effect on attitudes and values. Combat exposure was, however, limited during the deployments studied. Finally, the individual’s personality traits are identified as being relatively potent factors for inducing change and stability. By demonstrating that low-exposure PSOs have only minor effects on the sociopolitical psychological orientations of soldiers, the study advances knowledge of the political psychology of the peace soldier and provides additional contributions to the fields of value and personality psychology. Among other things, the study demonstrates the stability of values in a very challenging environment, and how personality traits affect change and stability in values.