Two patients are presented with central nervous system infections due to an uncommon type of viridans streptococci, S anginosus-constellatus. Of the various streptococci, S pneumoniae is the most common etiologic agent in meningitis, but many species, including those which are facultative anaerobes or microaerophiles, have been isolated from cerebrospinal fluid, subdural empyema, and abscesses involving the brain and epidural space.