Serious and life-threatening infections of the central nervous system (CNS) are frequently encountered in emergency departments (ED) and are associated with increased morbidity and mortality. CNS infections such as bacterial meningitis can often be rapidly progressive, resulting in permanent sequelae in a relatively short period of time. Although the availability of a variety of antibiotics has presumably made bacterial meningitis potentially curable, morbidity and mortality from this disease remains unacceptably high. (Quagliarello. VJ, Scheld WM. Treatment of bacterial meningitis. N Eng J Med. 2001;336:708-716). Hence, emergency medicine physicians must maintain a high index of suspicion for possible bacterial meningitis in patients who present to the ED with 1 or more of the following signs and symptoms: fever, headache, meningismus, altered level of consciousness, seizures, and neurological deficits, in order to enable the rapid recognition and prompt initiation of appropriate empiric broad-spectrum antimicrobial therapy. This article will highlight the epidemiologic trends, discuss the etiology and pathogenesis, clinical manifestations, diagnosis, and practical guidelines for the initiation of appropriate empiric antimicrobial regimens, and address controversial therapeutic adjuncts relating to the treatment of adult patients with bacterial meningitis.