Twelve patients with comorbid posttraumatic stress disorder (PTSD) and major depression underwent repetitive transcranial magnetic stimulation (rTMS) to left frontal cortex as an open-label adjunct to current antidepressant medications. rTMS parameters were as follows: 90% of motor threshold, 1 Hz or 5 Hz, 6,000 stimuli over 10 days. Seventy-five percent of the patients had a clinically significant antidepressant response after rTMS, and 50% had sustained response at 2-month follow-up. Comparable improvements were seen in anxiety, hostility, and insomnia, but only minimal improvement in PTSD symptoms. Left frontal cortical rTMS may have promise for treating depression in PTSD, but there may be a dissociation between treating mood and treating core PTSD symptoms.