This paper presents a rationale for acoustic analysis of voices of neurologically diseased patients, and reports preliminary data from patients with myotonic dystrophy, Huntington's disease, Parkinson's disease, and amyotrophic lateral sclerosis, as well as from individuals at risk for Huntington's disease. Noninvasive acoustic analysis may be of clinical value to the otolaryngologist, neurologist, and speech pathologist for early and differential diagnosis and for documenting disease progression in these various neurologic disorders.