Bystanders are an invaluable source of information about school bullying. Anti-bullying efforts to deliver justice are hampered if bystanders remain reluctant to discourage bullying; but given that bystanders who intervene to prevent bullying may be at increased risk of retaliation, why would they do so? This study aims to answer what promotes bystander intervention in the context of school bullying using a restorative justice approach. Data were collected through the Cross-national School Behaviour Research Project from 1,452 secondary school students (49% girls) in grades 7-10 in Bangladesh. Students who scored higher on school connectedness were more likely to intervene. High shame acknowledgement (accepting responsibility, making amends) and low shame displacement (blaming or hitting out at others) were also significant predictors of intervening in bullying. Regression analysis indicates that school connectedness compensates for the adverse effect of non-adaptive shame management (low acknowledgement and high displacement) on bullying prevention. Under a 'whole-of-school' approach, bystanders who can be referred to as 'soft targets' are moved more easily by a sense of collective shame/guilt and responsibility than 'hard targets' (such as bullies) whose emotional shell protects them from being ashamed/guilty. Establishing an ethical climate within schools that encourages a culture of mutual respect, shared responsibility and social inclusion may be a positive step towards promoting bystander intervention.