In this paper, we report the results of an experimental investigation of methane-air combustion within a porous medium burner for various equivalence ratios and flow rates. Measurements of emissions and radiant output are presented. The results indicate that CO and NOx, emissions increase with flame speed. For a given equivalence ratio, however, NOx, emissions are fairly constant over the range of flame speed studied. The radiant output increases but the radiant thermal efficiency decreases with flame speed.