In-vitro susceptibility of 299 Neisseria meningitidis and 157 Streptococcus pneumoniae strains from meningitis patients in The Netherlands in 1993 and 1994 to meropenem was determined using the Etest. Susceptibility to penicillin, ceftriaxone, and chloramphenicol was also determined. Rifampicin susceptibility was additionally tested for N. meningitidis. Of the meningococci, 4.3% were of intermediate resistance to penicillin and 0.3% were resistant to rifampicin. One pneumococcal isolate (0.6%) was of intermediate resistance to penicillin. All strains were susceptible to meropenem. We conclude that meropenem is in vitro highly active against N. meningitidis and S. pneumoniae.