Objective: To determine whether an early intervention using a psychological debriefing format is effective in preventing psychological distress in child road traffic accident survivors. Design: Randomised controlled trial. Setting: Accident and Emergency Department, Royal United Hospital, Bath. Subjects: 158 children aged 7-18. Follow-up assessment completed eight months post accident with 132 (70/82 of the experimental group and 62/76 in the control group). Main outcome measures: Self-completed measures of psychological distress; fulfilment of diagnostic criteria for post-traumatic stress disorder. Results: Children in both groups demonstrated considerable improvements at follow-up. The early intervention did not result in any additional significant gains. Conclusions: Although children in this study made significant improvements it is unclear whether these are better or worse than natural recovery rates. The specific intervention did not result in additional gains although the structured assessment provided for both groups may have been helpful in reducing subsequent pathology.