Although the effectiveness of cognitive-behavioral treatment in posttraumatic stress disorder (PTSD) is well established, few studies examined its effects on individual PTSD symptoms and possible mechanisms of improvement in symptoms. In a previous randomized controlled study [Başog lu, M., Salciog lu, E., Livanou, M., Kalender, D., & Acar, G. (2005). Single-session behavioral treatment of earthquake-related posttraumatic stress disorder: A randomized waitlist controlled trial. Journal of Traumatic Stress, 18, 1-11] a single session of behavioral treatment involving self-exposure instructions was highly effective in reducing earthquake-related PTSD. In the present study we examined the effects of treatment on each PTSD symptom and which symptoms improved early in treatment. Because the intervention focused solely on behavioral avoidance, we hypothesized that avoidance would be the first symptom to change and that reduction in avoidance would generalize to all other symptoms. The results showed significant between-groups treatment effect on only behavioral avoidance early in treatment (week 6). At 6 months post-treatment recovery rates ranged from 60% to 89% for 15 PTSD symptoms, including the numbing symptoms. Lack of improvement in avoidance was associated with lack of improvement in 12 symptoms. The critical process in recovery thus appeared to be increased sense of control associated with reduction in avoidance. These findings imply that live exposure to fear cues designed to enhance sense of control might be sufficient for recovery from PTSD.