A review of the world literature on the penetration (ratio of concentrations of cerebrospinal fluid to concentrations of serum) and attainable antibiotic concentrations in the cerebrospinal fluid in humans for cefuroxime, cefoxitin, cefotaxime, ceftizoxime, cefmenoxime, cefamandole, cefoperazone, moxalactam, ceftazidime, and ceftriaxone indicates that, with the exceptions of cefamandole and cefoperazone, all agents appear equivalent. We conclude that the choice of cephalosporin for the treatment of acute bacterial meningitis should depend mainly on the potency of the agent for the specific meningeal pathogens in question. For the treatment of common meningeal pathogens (Streptococcus pneumoniae, Haemophilus influenzae, and Neisseria meningitidis) and for gram-negative bacilli, mainly Escherichia coli and Klebsiella (excluding Pseudomonas aeruginosa), the cefotaxime-ceftriaxone group of cephalosporins has accrued the most clinical experience and the most pharmacokinetic data, while for P. aeruginosa the major interest has centered on ceftazidime.