The current study investigated moral disengagement, morally based self-esteem, age, and gender as predictors of traditional bullying and cyberbullying. The participants were 210 Australian school students aged 12 to 15, evenly split between males and females. Salient predictors of traditional bullying were overall moral disengagement, and the specific practices of moral justification and diffusion of responsibility. Furthermore, overall moral disengagement and the specific practices of diffusion of responsibility and attribution of blame predicted cyberbullying. Morally based self-esteem did not influence either form of bullying. Age predicted cyberbullying, with a greater tendency for older students to bully than younger students, while gender predicted involvement in traditional bullying, with boys more likely to bully than girls. Implications for antibullying interventions in schools are suggested. (Contains 3 tables.)