The management of acute traumatic cerebrospinal fluid (CSF) fistulae is still a matter of debate and hinges about what is perceived to be the risk of subsequent intracranial infection. We have therefore carried out a retrospective analysis of 160 cases of traumatic CSF leaks to assess the incidence, cumulative risk and prognosis of intracranial infection. The overall incidence of meningitis in this group before surgical dural repair was 30.6% (49/160), the cumulative risk exceeded 85% at 10 years follow-up and the meningitis was fatal in 4.1% (2/49). The recurrence of CSF leakage after initial spontaneous cessation was 7% and meningitis was recurrent in 30.6% (15/49). Prophylactic antibiotics had reduced the risk of meningitis from 61 to 34%. The commonest pathogen was pneumococcus and the CSF leakage had stopped within 7 days in 60% of those who developed meningitis and in 50% of those who did not develop meningitis. Meningitis is still a serious complication of post-traumatic CSF fistulae and is potentially fatal despite modern therapeutic agents.