Bacterial meningitis and viral encephalitis are life-threatening infections with high mortality rates. Patients who survive these infections often remain permanently disabled. Potential neurologic complications requiring careful attention include impaired consciousness, elevated intracranial pressure, hydrocephalus, stroke, and seizures. Systemic complications are also common and are frequently the immediate cause of death. Critical care of these patients should focus not only on treatment of the underlying infection and its immediate complications but also on minimizing secondary brain injury. Given the increasing complexity of the diagnostic and therapeutic modalities available in managing central nervous system infections, the involvement of neurocritical care units and neurointensivists may be particularly helpful in improving outcomes.