A frequent criticism of the Illinois Test of Psycholinguistic Abilities (ITPA) has been that it may measure general cognitive abilities — similar to the Wechsler Intelligence Scale for Children (WISC) or Stanford-Binet Intelligence Scale — rather than the specific abilities it was designed to measure. This study investigated the extent to which information obtained from the WISC overlaps with information obtained from the ITPA. A canonical correlation analysis revealed that only 24% of the WISC subtest variance is redundant, given the ITPA; while 22% of the ITPA subtest variance is redundant, given the WISC. The ITPA and WISC seem to measure essentially different constructs. The only subtests significantly related are the Digit Span and Auditory Sequential Memory subtests. Thus, an educational evaluator should not consider discarding one or the other test because of assumed similarity of results; both tests should be retained.