This prospective study of 276 Virginia public high schools found that the prevalence of teasing and bullying (PTB) as perceived by both 9th-grade students and teachers was predictive of dropout rates for this cohort 4 years later. Negative binomial regression indicated that one standard deviation increases in student- and teacher-reported PTB were associated with 16.5% and 10.8% increases in the number of dropouts, respectively, after controlling for the effects of other predictors, including school size, student body poverty and minority composition, community crime rates, and performance on standardized achievement testing. The predictive values of student and teacher perceptions of PTB were comparable in magnitude to the predictive values for other commonly recognized correlates of dropout rates. These results provide new evidence that the prevalence of peer victimization in high school is an important factor in high school academic performance.