Seventy-two male and 73 female undergraduates were randomly assigned to an experimental group, in which they wrote expressively about a relationship breakup, or to a control group, in which they wrote in a non-emotional manner about impersonal relationship topics. Control participants reported short-term increases in upper respiratory illness (URI) symptoms, tension and fatigue, whereas experimental participants did not. Further, higher levels of intrusive thoughts and avoidance were associated with short-term increases in URI symptoms in the control group, but were unrelated to URI symptoms in the experimental group. Finally, there was a trend ( p <0.06) suggesting that experimental participants were more likely to reunite with their ex-partner than were control participants. These findings indicate that expressive writing has a wide range of social, emotional, and physical health benefits for individuals coping with stressful events, particularly if they are experiencing ongoing intrusive thoughts and avoidance responses related to the stressor.