This study examined the relationship between performance on measures of attention and executive functioning in a clinically referred pediatric sample. The purpose of this research was to determine if performance on tests of attention are significantly related to performance on measures of inhibition and cognitive shifting above and beyond that of age, education, and intelligence. The factor structure of attention and executive functioning was also evaluated. Attention was measured by the CPT-II Errors of Omission and Variability scores. Inhibition was measured by the CPT-II Errors of Commission score, and cognitive shifting was measured by the Wisconsin Card Sorting Test (WCST) Perseverative Errors score. These variables were examined in a factor analysis, and also included the Category Errors score, and WISC-IV Digit Span, and Letter-Number Sequencing subtests. Three hierarchical multiple regressions were conducted, with age, education, and IQ entered in the first block as covariates. Two exploratory factor analyses were performed. Results revealed that performance on measures of attention significantly predicted scores on a measure of inhibition above and beyond age, education, and IQ. Performance on measures of attention did not significantly predict scores on a measure of shifting ability. Results were not significantly different when IQ was not included as a covariate. Factor analysis initially revealed a two factor model, with measures of sustained attention loading on one factor, and measures of executive functioning loading on a separate factor. The three factor model was less precisely defined, and the factors were called sustained attention, working memory, and set shifting.