Introduction: Older adults use the emergency department (ED) at high rates, including for illnesses that could be managed by their primary care providers (PCP). Policymakers have implemented barriers and incentives, often financial, to try to modify use patterns but with limited success. This study aims to understand the factors that influence older adults' decision to obtain acute illness care from the ED rather than from their PCPs., Methods: We performed a qualitative study using a directed content analysis approach from February to October 2013. Fifteen community-dwelling older adults age≥65 years who presented to the ED of an academic medical center hospital for care and who were discharged home were enrolled. Semi-structured interviews were conducted initially in the ED and subsequently in patients' homes over the following six weeks. All interviews were audio-recorded, transcribed, verified, and coded. The study team jointly analyzed the data and identified themes that emerged from the interviews., Results: The average age of study participants was 74 years (standard deviation ±7.2 years); 53% were female; 80% were white. We found five themes that influenced participants' decisions to obtain acute illness care from the ED: limited availability of PCP-based care, variable interactions with healthcare providers and systems, limited availability of transportation for illness care, desire to avoid burdening friends and family, and previous experiences with illnesses., Conclusion: Community-dwelling older adults integrate multiple factors when deciding to obtain care from an ED rather than their PCPs. These factors relate to personal and social considerations, practical issues, and individual perceptions based on previous experiences. If these findings are validated in confirmatory studies, policymakers wishing to modify where older adults receive care should consider person-centered interventions at the system and individual level, such as decision support, telemedicine, improved transport services, enhancing PCPs' capabilities, and enhancing EDs' resources to care for older patients., Competing Interests: Conflicts of Interest: By the WestJEM article submission agreement, all authors are required to disclose all affiliations, funding sources and financial or management relationships that could be perceived as potential sources of bias. This research was funded by the University of Rochester Provost’s Multidisciplinary Award, the University of Wisconsin-Madison School of Medicine and Public Health Shapiro Summer Research Program, and the Wisconsin Academy for Rural Medicine.