This study examined the convergent relations between scores from four clinical clusters from the Woodcock-Johnson III Tests of Cognitive Abilities (WJ III) and measures of executive functions using a sample of school-aged children and a sample of adults. The WJ III clinical clusters included the Working Memory, Cognitive Fluency, Broad Attention, and Executive Processes clusters, and the measures of executive functions were from the Delis-Kaplan Executive Function System (D-KEFS). Across both samples, all clinical clusters demonstrated evidence of statistically significant and moderate positive relations with at least some measures of executive functions. The Executive Processes cluster demonstrated relations with measures of executive functions that tended to be the strongest and most consistent of the WJ III clinical clusters. When these relations between the clinical clusters and the measures of executive functions were contrasted with the relations between the WJ III Comprehension-Knowledge cluster and the same measures of executive functions, results called into question the distinction between process and content but suggested that there is a common ability or common abilities underlying performance across all of the WJ III and D-KEFS measures. (Contains 3 tables and 1 figure.)