The European Huntington's Disease Network (Euro-HD or EHDN) is a Europe-wide network of professionals and people affected by Huntington's disease, who collaborate to organise and perform research into the condition, and improve the care of HD-affected individuals. The European Huntington's Disease Network (Euro-HD or EHDN) is a Europe-wide network of professionals and people affected by Huntington's disease, who collaborate to organise and perform research into the condition, and improve the care of HD-affected individuals. Huntington's disease (HD) is an incurable, genetically inherited degenerative brain condition that causes progressive impairment of motor function and cognitive decline and psychiatric symptoms. EHDN was founded in 2003 and is financially supported by the CHDI Foundation. EHDN provides an infrastructure for multi-national observational studies and interventional clinical trials in HD; organises biannual plenary meetings attended by professionals and HD family members; supports a range of working groups focusing on aspects of the disease; and provides endorsement and seed funding for individual research projects. At December 2011, EHDN had over 1000 regular members in 26 countries. EHDN's activities are governed by an elected Scientific and Bioethics Advisory Committee and an Executive Committee. The core project of EHDN is the REGISTRY study, a multi-national observational project that aims to study the natural history of HD and expedite recruitment of suitable volunteers into clinical trials. At December 2011, REGISTRY had enrolled over 7700 subjects in 145 sites, and generated nine peer-reviewed publications. The MermaiHD study of pridopidine and HORIZON study of latrepirdine in Huntington's disease were coordinated in Europe by EHDN.