In order to understand the longitudinal relationships between adolescent psychopathy, bullying perpetration, sexual harassment, and homophobic taunting, data were analyzed from surveys of 544 Canadian teenagers from grades 9 to 12 who took part in the ongoing McMaster Teen Study. The researchers hypothesized a pathway in which psychopathy and bullying were interrelated predictors of sexual harassment and homophobic taunting. Path analysis revealed that the model demonstrated excellent fit and had a significant effect of gender. Psychopathy and bullying perpetration were stable, covarying constructs and psychopathy predicted bullying throughout adolescence. Bullying was more strongly predictive of and concurrently related to homophobic taunting for boys than girls, and homophobic taunting was linked to sexual harassment perpetration for boys, but not girls. Psychopathy predicted homophobic taunting and sexual harassment equally across sexes. Limitations and future directions are discussed and suggestions for counselling adolescents who are high on bullying and psychopathic traits are provided.