Background: Experiencing adverse experiences during childhood can lead to the development of mental disorders. We therefore set out to identify that effectively help children who have experienced trauma.Methods: We used systematic review methods to identify randomized controlled trials (RCTs) evaluating prevention interventions for children after serious adverse experiences. After applying our rigorous inclusion criteria, we accepted five RCTs – evaluating three psychosocial interventions delivered to children who had been maltreated, and one medication for children who had sustained physical injuries.Results: It's My Turn Now, Fostering Healthy Futures, and Multisystemic Therapy showed benefits for children who had a history of maltreatment, including reducing symptoms of mental disorders. In contrast, Propranolol failed to show benefit for children who had sustained injuries.Conclusions: Preventing childhood adversities wherever possible is crucial and recognizes children's rights to safety. Yet it is possible to prevent mental health symptoms from developing even after children have experienced serious adversity.