Aid workers offer important perspectives for better understanding the most pervasive challenges that arise when implementing emergency response programming in humanitarian settings. This study provides a global review of these perspectives, derived from 4,679 applications of aid workers applying to the National NGO Program on Humanitarian Leadership (NNPHL), in which applicants were asked to respond to the question, “What do you consider to be the biggest challenges in the implementation of emergency response programming in today's humanitarian settings.” Through a qualitative coding process, the research team identified 14 major challenges that were pervasive across the applicant responses and cross-tabulated these with applicant demographics. Coordination (30%) and the operating environment (29.5%) were the most frequently reported challenges by the applicant pool. The study finds a significant association between challenges identified and certain demographic variables, including region of applicant origin, type of organization worked at, and number of years of experience. The results produced by the study's large sample size and methodology supplement a body of literature that is largely made up of small-scale, context specific studies in which disaggregation of data by demographics is not possible.