The performance of moxalactam with the BD Phoenix system for the detection of methicillin resistance in coagulase-negative staphylococci was evaluated by use of a collection of 186 strains. Moxalactam was a better drug as an indicator of methicillin resistance for mecA-positive strains than oxacillin and cefoxitin were. For strains other than Staphylococcus saprophyticus, a moxalactam MIC >16 microg/ml was indicative of methicillin resistance.