This investigation was a preliminary attempt to examine the response variability on word fluency measures that had been reported in previous studies. Three word fluency tasks were administered to five acute aphasic left CVA subjects, five chronic aphasic left CVA subjects, five acute nonaphasic right CVA subjects and five neurologically normal subjects during five sessions over a maximum 2-week period. All groups demonstrated response variability in the total number of words produced on each of the three word fluency tasks across the five sessions, confirming previous investigations that suggested that a single administration of such tasks is not a reliable measure of an individual's performance. Implications for interpreting a subject's score on word fluency tasks are discussed.