Bullying has been described as one of the most common and potentially serious forms of school violence. It is a pervasive problem affecting many students with serious adverse consequences for some. Given the prevalence of and consequences associated with bullying, we investigated the concept of bullying as applied to school settings. In this article, we discuss the need for an expanded definition of bullying, including particular considerations for differential behaviors between genders. Best practices for primary, secondary, and tertiary prevention of bullying behaviors in schools, and implications for school psychologists are also discussed. © 2004 Wiley Periodicals, Inc. Psychol Schs 41: 887–897, 2004.