Objectives Intrusive thoughts are common distressing symptoms that occur after exposure to stressful life events. This study tested the idea, based on metacognitive theory, that such intrusions may be ameliorated by the Attention Training Technique (ATT; Wells, ). Method Participants who reported distressing intrusions were randomly allocated to two sessions of ATT (plus homework) or a filler task and were exposed to a narrative recording of their traumatic experience before and after the intervention. Frequencies of intrusions occurring during the narrative were measured. A measure of self‐reported attention flexibility was also examined. Results Participants in the ATT condition showed a significant reduction in intrusion frequency and an increase in attention flexibility compared with the control group. ATT was associated with a 3.4 times greater reduction in the incidence of intrusions. Conclusions ATT may be an effective technique for reducing symptoms of stress exposure, reducing the incidence of intrusions when exposed to stimuli associated with stressful events.