The Commitee of Haemophilia of the GTH has established a central registry for all German centers treating patients with haemophilia. The intention was to establish a suitable system for collecting and analyzing epidemiological data relevant to bleeding disotders. The registry provides the database within the scope of the German Human-Genome-Project. The set goal is the complete molecular characterization of the genetic mutations on chromosome X of haemophilia A patients in Germany and subsequent correlation with the phenotype. An electronic network is applied for communication. A Java-application was developed for online electronic data acquirement by the participating centers. Offline data entry and sending encrypted datacenters is possible, too. A high level of security is assured by personalized access. Data are anonymized and scrambled by secute encoding. The concept was confirmed by the official data security offices. A considerable improvement for the epidemiological sciences and a better basis on therapy for patients with bleeding disorders is expected. Furthermore the registry is available for other scientific projects.