Adolescent bullies often grow into adult bullies, who then have children who are bullies. Bullies are disproportionately from lower socioeconomic status families characterized by poor parenting techniques, have high levels of impulsiveness, and are often unsuccessful in school. Victims of bullies seem to be unpopular and rejected by their peers and have low school attainment, low self-esteem, and poor social skills. Victims also tend to have children who are victimized. This essay discusses the epidemiology of bullying, including definitions, issues of measurement, reliability and validity, the prevalence and frequency of bullying, the overlap between bullies and victims, and the career paths of both parties. The author covers characteristics of bullies and victims, environmental considerations, and the consequences of bullying and victimization. New research provides evidence of intragenerational continuity and intergenerational transmission of bullying and victimization. Recommendations for bullying prevention and directions for future research are outlined. 3 tables, 157 references, and 1 appendix