The aim of our study was to explore students' bystander roles in peer bullying considering the interaction between their individual and contextual characteristics. We included social status goals (popularity, social preference and social insecurity), moral disengagement and peer support as key variables for differentiating bystander behaviour. Our sample comprised 5148 students from the 8th and 9th grades across 118 primary schools in Slovenia. Bystander roles (active and passive reinforcers, ignorants and defenders) were determined by peer nominations. Other characteristics were measured with self-report questionnaires. For each variable, we normalized students' results with regard to their classroom to define classroom norms as the context of peer bullying resulting in "low", "average" and "high" group. Students with similar individual and contextual characteristics were grouped into four clusters. The results showed that students from all clusters were present in all bystander roles, which indicates a highly complex interaction of various factors in bystander behaviour. Some educational implications are discussed.