Uncertainty and doubt dominate all aspects of tuberculous meningitis (TBM). The variable natural history and accompanying clinical features of TBM hinders the diagnosis. Ziehl-Neelsen staining lacks sensitivity and culture results are often insufficiently timely to aid clinical judgement. New rapid diagnostic methods are incompletely evaluated, and many are not suitable for laboratories in low income countries. The duration of chemotherapy for TBM is unclear and the benefits of adjuvant corticosteroids remain in doubt. The only uncomfortable certainties lie in the fatal consequences of missed diagnoses and delayed treatment. This review will discuss the current uncertainties surrounding TBM. More attention will be given to diagnosis and management, as these areas have a direct bearing on patient outcome.