The best approach for implementing early psychological intervention for anxiety and depressive disorders after a traumatic event has not been established. This study aimed to test the effectiveness of a stepped model of early psychological intervention following traumatic injury. A sample of 683 consecutively admitted injury patients were screened during hospitalization. High-risk patients were followed up at 4-weeks postinjury and assessed for anxiety and depression symptom levels. Patients with elevated symptoms were randomly assigned to receive 4–10 sessions of cognitive–behavioral therapy (n = 24) or usual care (n = 22). Screening in the hospital identified 89% of those who went on to develop any anxiety or affective disorder at 12 months. Relative to usual care, patients receiving early intervention had significantly improved mental health at 12 months. A stepped model can effectively identify and treat injury patients with high psychiatric symptoms within 3 months of the initial trauma.