 In recent years considerable efforts have been made to increase public awareness about depression and increase access to services. However, the increasing number of patients accessing treatment for depression in clinical services is also likely to be accompanied by a sizeable increase in the number of patients with TRD. Despite the demand, relatively few treatment options are available to such patients. One of the only substantially new treatments developed for TRD in recent years has been the advent of repetitive transcranial magnetic stimulation rTMS. Repetitive TMS has been evaluated in over 20 trials conducted over the last 10 years. Previous research indicates that rTMS has antidepressant activity; however, the proportion of patients who respond to rTMS and the degree of treatment response demonstrated in trials to date is limited. The limitations of these studies include relatively small samples and limited duration of treatment i.e., 2 weeks as well as a lack of long term follow-up. As rTMS is gradually entering use in routine clinical practice for example, recent regulation of its use in Canada, research is urgently required to establish ways to enhance treatment response both in regards to the extent of response within individuals and the proportion of individuals in whom rTMS has effects. 