School counselors influence the referral process and delivery of educational recommendations. Their perceptions of students' cognitive abilities are likely to influence their referral decisions as well as their interpretation and use of the results of psychological testing. The Cattell-Horn-Carroll, (CHC), model of intelligence, is gaining acceptance owing to a growing mass of evidence supporting the theory's diagnostic validity and potential utility in the field of education. The research on the ecological validity of CHC theory has looked only at teachers and school psychologists. This quantitative, quasi-experimental research compared school psychologists' and school counselors' understanding of cognitive ability as defined by CHC theory, and examined whether education level and experience were related to respondents' understanding of CHC cognitive abilities. A sample of 528 participants completed a demographic questionnaire and a 34-item sorting task that involved identifying CHC cognitive abilities as they relate to common academic tasks. These data were analyzed using independent t-tests and 2-way ANOVA. As hypothesized, school psychologists demonstrated a higher ability to identify CHC Broad as well as specific broad cognitive abilities, with the exception of short-term memory, which school counselors were equally able to identify. School psychologists' superiority in identifying CHC Broad abilities was demonstrated by the very large effect size of the difference between group means. Effect sizes for differences in ability to identify specific broad stratum cognitive abilities (with the exception of short-term memory) were small or medium, except for crystallized ability, which was large. Counter to expectation, experience and education did not exert an influence on participants' abilities to identify CHC Broad or specific broad abilities. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]