Most research on workplace aggression focuses on the antecedents and consequences of aggression for individual workers. The current study examines how shared workplace aggression concerns relate to internal and external organizational outcomes. Drawing on the work stress, social identity, and social contagion literatures, we propose relationships between unit-level aggression concerns and unit-level measures of performance and employee attitudes in a public school sample (2989 employees; 163 schools). We also propose that these relationships differ depending on the resource context of the school. Consistent with our expectations, schools in which teachers had strong shared concerns about aggression also had poorer shared job attitudes and poorer student outcomes, as indicated by average standardized test scores at the school. The impact of shared concerns about aggression on school-level standardized test scores was stronger for resource-rich schools than for schools with fewer resources. The current study contributes to organizational research as it establishes that workplace aggression concerns have adverse consequences for the whole organization, not only for the individuals experiencing the events. Our findings demonstrate that employees' shared concerns about aggression have an impact on organizational outcomes and suggest a prevention-focused approach to workplace aggression. Copyright © 2012 John Wiley & Sons, Ltd.