Aid workers experience elevated levels of stress which has a detrimental impact on individuals, organisations and the aid sector; however, there is limited qualitative research capturing aid worker's views on stressors and coping strategies. This study used thematic analysis to examine aid workers' views on three research questions: their most common stressors, effective coping strategies and ineffective coping strategies. The study involved a wide range of aid workers (N = 218) living in 63 countries, including previously under-researched groups such as development professionals and national workers. Four overarching themes emerged across the three research questions: Work, Psychological, Lifestyle and Social Connection. The most common stressors were work-based issues such as workload, managers and colleagues. Key effective coping strategies were social connections and lifestyle activities such as exercise and hobbies. Ineffective strategies were lifestyle activities such as alcohol and unhealthy eating, and workbased strategies such as working harder. Investigation of aid workers' views through a qualitative approach rather than quantitative scales yielded important new insights such as the high prevalence of work and team stressors, infrequent mention of trauma as a stressor, the important role of psychological support, the importance of meaningful work and the observation that coping mechanisms can be both effective and ineffective depending on context. We used additional quantitative analysis to identify many differences between national and international workers but few between humanitarian and development professionals. Regarding theoretical implications, coping strategies were effectively mapped on to the psychological flexibility framework, which underpins acceptance and commitment therapy. We also use the findings to inform practical stress reduction recommendations at the individual, organisational and sector levels. By giving a voice to aid workers, this research extends our understanding of stress and coping within the aid sector, with the potential to enhance aid worker wellbeing and the delivery of aid.