Emergency department (ED) violence is a significant problem in many hospitals. This study identified the incidence of violence by patients towards nurses in two EDs. Patient factors related to violence were identified and the circumstances surrounding the violent incident were described. Of the 71 ED nurses who participated, 50 (70%) reported 110 episodes of violence in a five-months period. That is approximately five violent incidents per week. Violence was reported most often on evening shifts (n=41, 37%). The nurses' perceived that the perpetrators of violence were under the influence of alcohol (n=30, 27%) and drugs (n=27, 25%) and displayed behaviours associated with mental illness (n=42, 38%). Nurses in this study were sworn at (n=67, 61%), pushed (n=11, 10%), hit (n=3, 3%), and kicked (n=3, 3%). Identification of trends and patterns of violence is necessary so that better health care planning and service provision as well as effective preventative and safe strategies for nurses in the workplace can be implemented.