This article provides a clinical and cognitive neuropsychological analysis of a patient who presented a marked and progressive linguistic disturbance in the absence of any other significant cognitive impairment. A PET scan indicated that this disorder was associated with focal left temporofrontal hypometabolism. The essential characteristics of this disorder were anomia, surface dyslexia, and surface dysgraphia, along with a mild grammatical disturbance and deficits in both visual and auditory word comprehension. The patient's disorder is considered in relation to other similar cases and to modular accounts of acquired linguistic disorders. © 1993 Academic Press, Inc.