Although bullying was once considered to be a social problem unique to childhood, research conducted during the last few decades has suggested that the behaviors associated with bullying continue into adulthood. Bullying is a form of instrumental aggression, meaning that it is proactive and frequently not a response to aggressive behavior demonstrated by a victim (Espelage and Swearer, 2003). Also, a power differential exists between the perpetrator and victim, and results in the victim feeling unable to defend him or herself from the bully’s aggression (Espelage and Swearer, 2003). Bullying behavior tends to be repeated over time, although in some cases, a single incident can also be seen as an instance of this type of aggression (Olweus, 1993).