It has been suggested that patients with Parkinson's disease might show the same kinds of behavioural impairments as those exhibited by subjects with frontal lesions. Previous tests of this hypothesis have given, at best, equivocal results. Verbal fluency is a measure sensitive to frontal lesions, and data are presented showing that Parkinsonian subjects produce fluency scores similar to those of normal controls and not at all like subjects with left or right frontal lesions.