The purpose of this review was to summarize the findings of published reports that investigated quality-related outcomes and emergency department (ED) crowding. Of 276 data-based articles, 23 reported associations between patient outcomes and crowding. These articles were grouped into 3 categories: delay in treatment, decreased satisfaction, and increased mortality. Although these studies suggest that crowding results in poor outcomes, it is possible that other factors such as nursing care contribute to these adverse outcomes. Nursing care has been shown to contribute to both positive and negative patient outcomes in other settings. Building an understanding of how ED crowding affects the practice of the emergency nurse is essential to examining how nursing care, surveillance, and communication impact outcomes of emergency patients. Investigation into nurse-sensitive quality indicators in the ED has potential to develop strategies that deliver high quality of care, regardless of crowded conditions.