The principle of distinguishing between selective memory deterioration and global intellectual decline has been applied to 38 patients with alcoholic Korsakoff's syndrome. Indices were developed for each type of deficit and their distributions explored. Considerable variation was seen in both parameters, the transition from pure memory loss to global intellectual deficits appearing to be gradual. Differences were found in the sex and CT scan associations of the indices. The implications of the distinction for future research are discussed.