The research objective of this contract is to continue to maintain and expand a voluntary roster of patients and families affected by Huntington's Disease. The Contractor shall collect data on persons with Huntington's Disease, persons at risk of the Disease, and people related to those with or at risk of Huntington's Disease. The Roster will be used to contact potential participants for research studies, to locate individuals of particular research interest, and to provide statistical and demographic data on Huntington's Disease. The research roster of patients and families affected by Huntington's Disease is expected to continue to be a valuable resource for future research.