Bacterial meningitis is an infection of the central nervous system involving quite a number of neurological sequelae the most common of which is hearing impairment. To assess the incidence of audiological deficit the authors evaluated retrospectively 20 patients, between 4 months and 11 years of age, observed at the Pediatric Clinic at the University of Pisa between 1988 and 1993. A clinical-neurological examination and a complete auditory assessment (using BAEPs and impedence audiometry) has been performed in every patient between 1 and 18 months after they left hospital. 4 children had persisting neurological sequelae, 3 patients developed sensorineural hearing loss and one child visual impairment and seizures. Haemophilus Influenzae was responsible for 2 cases of sequelae and Streptococcus Pneumoniae for the other 2 cases. The number of days of illness before hospitalization and the institution of an antibacterial treatment, persistence of fever and deviation from the normal level of consciousness and persistence of neck rigidity were not correlated with the presence of sequelae. No correlation has been found between sensorineural hearing loss and the kind of antibacterial therapy. It's advisable that every child, following bacterial meningitis, should undergo a complete and repeated audiological assessment to detect any lesser impairments and/or unilateral losses that may damage the development of speech and language in any way.