Transcranial magnetic stimulation (TMS) is a well-established diagnostic probe in neurological practice. The increasing knowledge of biological mechanisms in electroconvulsive therapy presents a clear case for studying the applicability of TMS as a therapeutic tool in psychiatry. Based on the results of our pilot study showing a possible antidepressive effect of TMS, we conducted a controlled clinical trial on patients affected by major depression (DSM-III-R). Group 1 (n = 12) underwent TMS as add-on therapy to standard antidepressive medication, while group 2 (n = 12) was treated only with antidepressive medication. Already after the third add-on TMS session, a statistically significantly greater remission of depressive symptoms occurred in the patients of group 1 (p = 0.003). This statistically significant difference between the groups became even more marked on the last day of the study (p = 0.001, Wilcoxon). The results and further implications of TMS in psychiatric disorders are discussed.