Huntington's disease may present at any age, but most typically manifests between the ages of 35 and 45 years as a slowly progressive neurodegenerative movement disorder with cognitive and behavioral impairment. It is an autosomal-dominant disorder that has a substantial impact on family structure and dynamics in terms of providing care for affected family members and, for the offspring of an affected parent, dealing with at-risk status. Therapy that slows the progressive neuronal dysfunction or degeneration is unavailable, so pharmacotherapy is currently aimed primarily at managing behavioral and psychiatric symptoms, and, in selected cases, controlling severe chorea. Effective intervention by clinicians is possible, however, in terms of providing patients and families with accurate information about the disease, counseling them about availability of genetic testing at specialized centers, and in giving them sound advice regarding work, driving, relationships, finances, research participation, and support groups.