Citrobacter meningitis is an uncommon enteric gram-negative infection that afflicts neonates and young children. Approximately 30 percent of children treated or untreated die from the infection. We report a case of C. freundii meningitis that was resistant to ampicillin and was successfully treated with ceftriaxone, a third-generation cephalosporin. A 13-day-old, full-term baby was admitted to the hospital with a one-day history of fever up to 38.8 degrees C. On admission the infant had a temperature of 39.2 degrees C, pulse of 140 beats/min, and a respiratory rate of 32 breaths/min. Except for a slightly bulging fontanelle, the rest of the physical examination was within normal limits. Complete blood count revealed a white blood cell (WBC) count of 12.5 x 10(9)/L, with 0.66 polymorphonuclear cells, 0.10 bands, 0.18 lymphocytes, and 0.06 monocytes. A stat lumbar puncture showed 10 WBCs per high-power field with gram-negative rods. Empiric therapy with ampicillin 225 mg q12h and gentamicin 11 mg q8h was started. Both antibiotics were discontinued after culture and sensitivity results were positive for C. freundii in the blood and spinal fluid. The patient was successfully treated with nine days of ceftriaxone 250 mg q12h.