In this study, 60 patients were randomized to either HFL-TMS or LFR-TMS or a sham stimulation condition (n=20 in each group). All had treatment resistant depression (TRD) and had failed multiple antidepressant medication trials (mean number = 5.7 ± 3.4). There were no baseline clinical or demographic differences between the three groups. Over the double blind phase of the study there was clearly an antidepressant effect of both active groups that was superior to the response to sham stimulation. There was a continued improvement in both active groups across the 4 weeks of the study: for the group as whole, after the 4 weeks of treatment the mean percentage change in MADRS score from baseline was 48.0 ± 17.9% (range 15.1 - 87.5%). These results demonstrated that both HFL-TMS and LFR-TMS have substantial therapeutic efficacy and that robust clinical response appeared to require at least 20 sessions of treatment with the parameters used. However, only a sub-population of patients responded to treatment.