Four strains of coagulase-negative Staphylococcus spp. were isolated from blood cultures taken from two neutropenic patients; in three cases while they were receiving teicoplanin as part of an antimicrobial therapeutic regimen. Results of teicoplanin susceptibility tests carried out on these strains varied according to the technique used. The strains were susceptible by disc-diffusion testing, but the MIC of teicoplanin was 8-16 mg/l, when tested according to the recommendations of the Antibiogram Committee of the French Society of Microbiology, and thus categorized as of intermediate susceptibility. It seems reasonable to avoid using teicoplanin for the treatment of infections caused by coagulase-negative staphylococci until technical problems encountered in the in-vitro determination of susceptibility have been resolved.