Auditory discrimination abilities of professional musicians were compared with those of nonmusicians. The stimuli for the frequency‐discrimination tasks were 300‐msecsinusoidal tones, 300‐msec square waves, and tone patterns consisting of ten 40‐msec tones played sequentially. The musicians’ difference thresholds for single tones were betweenΔf /f=0.001 and 0.0045. One‐half of the nonmusicians attained thresholds almost as low; the rest attained larger thresholds, up toΔf /f=0.017. The results for the pattern stimuli show a clearer separation between the nonmusicians and musicians, whose median differencethresholds were about three times smaller. However, nonmusician listeners who had previously trained with patterns not in the test set had different thresholds,substantially smaller than those obtained by the musicians. The appropriateness of preferential recruitment of musicians for psychoacoustic research is discussed. The responses to amusical background survey and correlations between the survey items and discrimination performance are contained in a supplement to this paper [PAPS JASMA76, xxx‐xx].