Do people have expectations about the frequency of occurrence of consonants in a given context and if so, do such expectations manifest themselves as consistent response biases in perceptual confusions? Subjective estimates of the frequency of selected /ιC/ syllables in English were measured. Subjects were auditorily presented with pairs of syllables and were asked to judge which member of the pair was the more frequent sound sequence in English. The scaled frequency judgments correlated highly (r= 0.84,p<0.001) with consonant frequencies in the same environment in published counts, Available data on perceptual confusions was analysed to determine if there was any consistent response bias. Consistent differences among various consonants in terms of their tendency to occur as responses would constitute a response bias. The number of times a certain consonant was given as a response in the material examined did not correlate with that consonant's frequency of occurrence. Such consistent response biases as did occur were due to asymmetric relations within a small subset of the total set of consonants. [Work supported by NSF, Z.W.O.]