Three judges rated a number of speech characteristics of 20 patients with Wilson’s disease, an inherited metabolic disease. The perceptual data suggest the presence of a mixed dysarthria with prominent ataxic, spastic, and hypokinetic features which were predictable from neurologic data on the patients. Perceptual data on 10 patients, recorded at two specific points in a treatment program, indicate that speech can be used as an effective monitor of progress in the treatment of this disease.