Huntington disease (HD) is one of the most common autosomal-dominant monogenetic diseases with an adult onset. Clinically, HD is characterized by a combination of motor deficits, cognitive decline, and psychiatric abnormalities. The disease typically progresses over 15–20 years and usually leads to death arising from complications such as pneumonia due to dysphagia, or suicide. Although the causative mutation was discovered more than 25 years ago, so far no effective neuroprotective or disease-modifying treatment has been found. In this article, we present an overview of the clinical presentation, genetics, neuropathological, and molecular changes in HD in addition to novel treatment options. Moreover, we give a brief insight into relevant animal models and ongoing studies, and also present the special considerations for genetic counseling in terms of predictive and prenatal diagnostics.