<p>This study addresses the impact of witnessing different types of school bullying on Turkish school students who are bystanders. The primary aim is to investigate how the type of bullying (direct/indirect; ostracism/devaluation) affects the perception of bullying and the roles witnesses take. Additionally, we explore whether gender, global state self-esteem, and identification with one’s school account for variability in the dependent variables. Using an experimental vignette design, 378 Turkish students (mean age 15&#xa0;years, 59% female) from four schools were randomly assigned to one of four vignettes describing Direct/Ostracism, Indirect/Ostracism, Direct/Devaluation, and Indirect/Devaluation scenarios. Students perceived significantly less bullying in the indirect devaluation scenario compared to the other three conditions and had less reaction to it than the other conditions. Students who identified more strongly with the school were more likely to perceive that bullying was involved in the vignettes and they were also more likely to react negatively and less likely to remain passive. Girls were more likely to perceive the situations as involving bullying, while boys were more likely to react negatively to the bullying. Finally, self-esteem was not associated with type of bullying. The findings address a critical gap in the literature by examining the often-neglected impact of witnessing school bullying on bystanders and perceptions of different types of bullying.</p>