The place of repetitive transcranial magnetic stimulation (rTMS) in the treatment of depression remains unclear. In this sham-controlled study we determined the efficacy and acceptability of fast, left frontal rTMS given three times a week over 4–6 weeks to 29 patients with depression (79% treatment-resistant). The procedure was generally well tolerated and more effective than sham treatment (55 v. 7% responding, P<0.05), with improvement maintained to 12 weeks. This therapy could be a useful addition to available treatments but further research is needed to determine the optimum treatment parameters.