Relatively little research has been devoted to developing empirically-supported interventions for the secondary prevention of chronic post-traumatic stress disorder (i.e., for individuals who have developed PTSD symptoms but not the full PTSD disorder). One-session psychological debriefing has been routinely used as a primary preventive intervention for individuals exposed to trauma, but the appropriateness of this practice has been questioned. The authors describe an alternative, secondary prevention model of brief exposure- based treatment using three cases of military members seeking help at a forward-deployed medical clinic in Iraq for PTSD symptoms following combat -related traumas. Treatment involved repeated imaginal exposure and in vivo exposure conducted in four therapy sessions over a five-week period. Baseline measures on the PTSD Checklist were at a level that is considered to be in the range of PTSD. The results indicated that after four treatment sessions, PTSD symptoms were reduced by an average of 56%, and the final PTSD Checklist scores were within normal limits. The results suggest that prolonged exposure therapy may be a rapid individual treatment for the secondary prevention of combat-related PTSD.