Identified over a century ago, hereditary hemorrhagic telangiectasia (HHT), or Rendu-Osler-Weber syndrome, is an autosomal dominant condition characterized by multisystemic vascular malformations and hemorrhage from the associated vascular lesions. HHT may have first been described by Sutton1 and in turn, Babington,2 as a hereditary form of epistaxis. However, it was Rendu3 who first recognized the combination of hereditary epistaxis and telangiectases as a distinct clinical entity from hemophilia. At the turn of the nineteenth century, Osler4 and Weber5 produced case reports of inherited epistaxis and cutaneous and/or mucocutaneous telangiectases. Shortly thereafter, Hanes6 coined the term hereditary hemorrhagic telangiectasia using the three clinical features that at that time defined the disorder.