Although the phenomenon of crowding in emergency departments (EDs) is not new, it remains a significant problem for patients, ED staff and the wider healthcare system. Crowding in EDs, which is also called overcrowding, has been widely explored in the literature, but there are relatively few studies of the subject from an emergency nurse perspective. This article reports the findings of a literature review that aimed to explore the effects of crowding on nurses working in EDs. Four key themes were identified from a synthesis of 16 articles included in the review: staffing and skill mix; inadequate care and the effect on nurses’ well-being and stress levels; violence in the ED; and hospital metrics and patient flow. Further research is required to explore in more depth the effects of ED crowding on emergency nurses and to address the multiple factors that perpetuate the phenomenon.