Clinicians are often expected to project patients' clinical outcomes to allow effective planning for future care. This can be a challenge in patients with moderate to severe traumatic brain injury (TBI) who are often unable to participate reliably in clinical evaluations. With recent advances in computer instrumentation and signal processing, evoked potentials and event-related potentials show increasing promise as powerful tools for prognosticating the trajectory of recovery and ultimate outcome from the TBI. Short- and middle-latency evoked potentials can now effectively predict coma outcomes in patients with acute TBI. Long-latency event-related potential components hold promise in predicting recovery of higher order cognitive abilities.