Investigations were carried out concerning the selectivity and productivity of rabbit plasma fibrinogen (RPF) agar according to Beckers et al. Its selectivity was compared with pork plasma fibrinogen (PPF) medium according to Hauschild et al. and its productivity was compared with PPF medium and Baird-Parker''s egg yolk tellurite glycine pyruvate (ETGP) agar. In total, 139 samples of naturally contaminated foodstuffs were examined. RPF agar scored higher than ETGP agar; although only small (mean value of differences 0.09 log units), the differences were statistically significant. While no significant differences in sensitivity between RPF agar and PPF medium were encountered, RPF agar was statistically more selective than PPF medium. RPF agar is very suitable for the enumeration of S. aureus in foods.