When a client has cognitive impairment resulting from cerebral dysfunction (CD) that goes undiagnosed and, therefore, untreated, psychotherapy and rehabilitation outcome is likely to be impacted negatively. Due primarily to managed care, screening for CD has reduced substantially. Master's level counselors need a cost-efficient way to detect possible CD and, thus, justify referral for neuropsychological evaluation. This study examined the Wechsler Abbreviated Scale of Intelligence™ (WASI™) instrument's ability to screen for possible CD by examining the relationship between a) WASI Performance IQ (PIQ) and Verbal IQ (VIQ) scores and neuropsychological test scores, and b) the VIQ-PIQ discrepancy and the severity of disability. In this retrospective study, test scores were extrapolated from neuropsychological assessments conducted between 2001 and 2004 on 73 CD-diagnosed adults at a CARF accredited rehabilitation facility. Disability severity ratings of mild, moderate, and severe were assigned based on clinical judgment and interrater agreement. The assessment battery included the WASI and several neuropsychological tests: Halstead-Reitan TPT, TMT-A and B, and FOT; WMS-III VR-I and 2, LM-1 and 2, and MC; McCarron-Dial HVDT; SDMT; and SCT. Based upon a multitrait-multimethod matrix, mild to moderate convergent and discriminant validity was found with the WASI VIQ and PIQ traits among neuropsychological verbal …