Aggression in the workplace has increasingly become a focus of organizational behavior research given its debilitating effects on employees and consistent links to reduced organizational performance. The current literature on workplace aggression presents a bewildering array of definitions with overlapping meanings creating confusion for researchers and academics. In response to this, we consider a range of definitions of workplace aggression and build a taxonomy of workplace aggressive behaviors based on four dimensions: intensity, impact, intentionality, and indirect/direct aggression. This chapter contributes to the field offering a taxonomy of aggressive behaviors at work that can be used in subsequent research.