The value of neuropsychological assessment in the evaluation of attention disorders is based on assumptions that neuropsychological tests have sufficient sensitivity and specificity to identify specific and discrete patterns of neuropsychological performance associated with the behaviorally defined Diagnostic and Statistical Manual of Mental Disorders criteria. Neuropsychological instruments assessing attentional disorders purport to measure discrete executive management skills, and although there is ample research on the sensitivity of specific neuropsychological tests to damage to certain brain regions, a review of this literature indicates that these instruments are consistent neither in identifying specific regions nor in articulating functional deficits associated with lesions to these areas. We review a number of meta-analyses, which conclude that the assessment of executive functioning by neuropsychological tests inevitably leads to assessment of cortical-subcortical circuitry common to many forms of executive function and by implication, behavioral functioning. We argue that efficacy of neuropsychology is limited by its clinical and research participation in the current behaviorally constructed diagnostic system, which does not adequately or accurately reflect underlying neurophysiological or neuropsychological processes. Recommendations, including the development of a diagnostic nosology reflective of underlying neuropsychological processes, are made.