Fluency measures are commonly used in clinical developmental neuropsychology to assess executive functions. Little is known about the effect of age on performance in these tests. This article analyzes the effect of age on measures of verbal (semantic and phonologic) and nonverbal (semantic and nonsemantic) fluency in 171 children (81 boys, 90 girls) between ages 6 and 15. Participants were selected from public and private schools in Guadalajara and Tijuana, Mexico. A significant age effect was found on all tests but no interaction between age and type of test was found. Significant correlations among the 4 fluency tasks ranged from.36 to.46. Results are consistent with the findings of normative studies carried out in other countries and support the cross-language validity of verbal fluency tests.