Cognitive impairments related to alcoholism are examined in terms of input, intervening, and output variables. Respectively, the dysfunctions are represented by visuospatial/perceptual abnormalities, affective/conative deficits, and strong perseverative response tendencies. Defects in one or more of these aspects of cognitive functioning may appear as problems of memory. Functional differences between subgroups of alcoholics who do and do not develop severe anterograde amnesia characteristic of Korsakoff's syndrome presumably are attributable to differences in the distribution and extent of brain pathology. Both subgroups have widespread cortical pathology, which may play an important role in stimulus-processing deficiencies observed in both. Korsakoff's have demonstrated a more significant degree of pathology in diencephalic and basal forebrain structures than that observed in non-Korsakoff alcoholics; this may contribute to the greater memory and affective impairments in the former. However, in no subgroup of alcoholics can a single functional system or brain region be implicated as the major contributory factor. Rather, damage to multiple brain regions likely is responsible for the plethora of cognitive difficulties reported in the alcoholism literature.