The activity of combinations of vancomycin (2 or 10 ,ug/ml), gentamicin (0.3 ,ug/ ml), and rifampin (0.03 [xg/ml) against methicillin-resistant, coagulase-negative staphylococcal isolates was determined by the time-kill method. Combinations of rifampin with gentamicin or with vancomycin 2 ,ug/ml demonstrated enhanced killing against 13 of 17 and 13 of 25 strains, respectively. However, rifampinresistant strains were selected with the latter combination in the remaining 12 of 25 studies.