The purpose of this article is to outline the principles of transcranial magnetic stimulation (TMS), to summarize the existing use of TMS as a prognostic indicator and as a therapeutic device in clinical populations, and to highlight the potential of repetitive TMS (rTMS) as an intervention for traumatic brain injury. TMS is a painless method to stimulate the human brain. Repeated applications of TMS can influence brain plasticity and cortical reorganization through stimulation-induced alterations in neuronal excitability. Existing evidence has demonstrated positive outcomes in people with motor disorders and psychiatric conditions who have received rTMS as a therapeutic intervention. These findings suggest that rTMS may be a promising treatment for people with traumatic brain injury.