AbstractHemophilia and von Willebrand's disease are the most common congenital coagulation and bleeding disorders. The situation for patients suffering from these conditions has changed drastically during the last 2 to 3 decades. It is the purpose of this article, first, to give data on demography and mortality in hemophilia and, then, to review basic problems of therapy, especially in connection with surgery in hemophilia and von Willebrand's disease with emphasis on the use of blood components.