The activity of linezolid in comparison to vancomycin, teicoplanin, oxacillin, clindamycin and gentamicin was tested against 60 strains of methicillin-resistant Staphylococcus aureus, 60 strains of methicillin-resistant Staphylococcus epidermidis isolated from patients with nosocomial infections and 24 strains of vancomycin-resistant Enterococcus faecium isolated from feces of hospitalized patients. Minimum Inhibitory Concentrations (MICs) were determined by the Epsilometer test method. All tested strains were sensitive to linezolid and specifically all methicillin-resistant S. aureus had MIC range 0.25-3.00, MIC50 = 0.75, MIC90 = 1.5, all methicillin-resistant S. epidermidis had MIC range 0.125-1.5, MIC50 = 0.5, MIC90 = 1 and all vancomycin-resistant E. faecium had MIC range 0.5-1.5, MIC50 = 1, MIC90 = 1. Linezolid is the first of a novel antimicrobial class, the oxazolidinones, which is a promising treatment for serious Gram-positive infections, including multiresistant strains.