Huntington's disease is an autosomal dominant neuropsychiatric disorder which usually afflicts people with dependents. Psychiatric disorders figure prominently in the differential diagnosis, and may complicate the clinical picture, sometimes even antedating the onset of neurological signs. Diagnosis is still usually clinical, for which some knowledge of the disease is required. Positron emission tomography, where available, can assist in early detection. Recent scientific breakthroughs have considerably improved the accuracy of predictive genetics, and the psychological outcome of such testing may be better than previously, but considerable ethical dilemmas have yet to be fully addressed. Genetic treatment is being considered. Drug treatments offer crude symptomatic improvement. Counselling and support services are essential, as are voluntary self-help organisations. Specific day and inpatient facilities are sparse.