Discrimination of pitch for very brief tonal stimuli was measured in a two interval forced choice experiment in which experienced subjects were required to select the stimulus complex that contained acoustic events more disparate in pitch. Within each complex a comparatively long (750 ms) standard tone was followed by a 750 ms interstimulus interval and a brief comparison tone of variable frequency and duration (2, 4, 6. or 8 cycles). Frequencies used for the standard tone were 125, 250, 500, 1000, and 2000 Hz. All stimuli were matched for loudness. Analysis of performance indicates an interaction between number of cycles in the brief tone sample and frequency of the standard tone. Patterns of errors are considered in relation to spectral and periodicity models of pitch perception.