Acoustic reflex thresholds (ARTs) were determined at 0.5, 1, 2 and 4 kHz in 40 normal ears of college age subjects. Thresholds were redetermined at intervals of 3 min, 15 min and 1 week. Although statistical analysis revealed ARTs at 1 week to differ significantly from previously obtained values, this finding is not clinically significant as the greatest degree of variation was only 3.6 dB SL at 0.5 kHz. Furthermore, significant correlation coefficients at a particular frequency between times were obtained. The finding of a lack of correlation between frequencies serves to alert the audiologist to the potential error inherent to immittance screening programs which utilize reflex testing at one frequency only. The use of tympanometry and pure-tone testing in conjunction with reflexometry may reduce this potential error.