This study assessed the effectiveness of Greiffenstein's Reliable Digit Span (RDS) score for the detection of malingered neurocognitive dysfunction. Participants were 54 traumatic brain injury patients referred for neuropsychological evaluation. Twenty-four met the Slick, Sherman, and Iverson criteria for at least probable malingered neurocognitive dysfunction. The control group was composed of 30 patients without external incentive and who thus did not meet the Slick criteria. All patients completed the digit span test as part of either the WAIS-R or WAIS-III. The RDS scores were calculated, and sensitivity, specificity, and predictive power were examined for several cutoffs. Classification accuracy for the RDS was excellent. Issues related to the clinical application of this technique are discussed.