This study focused on verbal and physical aggression against nursing staff, in real time, by elderly patients. The aggressive incidents were recorded at the end of each shift when they were more likely to be accurately remembered. Before beginning the study, nursing staff were taught how to use the Modified Overt Aggression Scale (MOAS) to identify aggressive acts. High rates of verbal and physical aggression among the elderly were observed by nurses, and data show that 75% of nursing staff experienced aggression on their shift. They either experienced aggression themselves or observed aggression on every single shift; that is at least five violent incidents in a work-week. Even if one is not the target of aggression, such observation is associated with elevated levels of stress.