This study looks to contribute to not only identifying stressors experienced in the humanitarian context of working in displacement emergencies, but also how these stressors affect job performance outcomes of Stand-by Roster deployees specifically. With a pragmatist approach, the thesis uses a mixed-methods research design to investigate the research questions at hand by analyzing initial quantitative mission surveys, further supported by and expanded upon by the qualitative follow-up interviews with deployees. The results show that stressors identified by expatriate humanitarian workers align with those categorized by Cavanaugh et al.’s Challenge-Hindrance Stressor Framework including both challenge stressors (i.e. workload pressures) and hindrance stressors (i.e. role ambiguity, colleague behavior, resource inadequacy). Results also identified additional work-related stressors outside of this theoretical framework. Refuting what was originally proposed as a hindrance stressor for the purpose of this thesis, findings determined security risk stress as a challenge stressor instead. Stress related to short-term contracts remain inconclusive as a hindrance or challenge stressor. Findings also confirmed feelings of commitment as well as public service motivation acting as mediators.