The advent of very sensitive and rapid agglutination tests has been a major advance in facilitating the rapid diagnosis of bacterial meningitis (Table 3). Future investigations will focus on the use of monoclonal antibodies that have been found to be more sensitive and specific than polyclonal antiserums. Modifications of enzyme immunoassays of bacterial antigens to improve speed and technical reliability are in progress. The day may come with the present advances in technology that within 1 hour of receiving a CSF specimen, both the identity and antimicrobial sensitivity of the invading pathogen will be known to the physician. In addition, through quantitation of bacterial antigen, a reliable prognosis as to the outcome of the treated meningitis will also be possible. Finally, the continued refinement of reliable antiserums to group B Neisseria meningitidis, as well as other bacteria responsible for meningitis, particularly in the immunocompromised host will occur.