The Prevention of Complications of Hemophilia has established and coordinated a network of hemophilia treatment centers (HTCs) to promote the management, treatment, and prevention of complications experienced by persons with hemophilia and other hereditary bleeding disorders. This program developed a system to monitor blood safety and conduct health-care-outcome research, collaborated with the National Hemophilia Foundation in developing a national health campaign to encourage individuals to adopt healthy behaviors and participate in the HTC network and established a reference library to diagnose rare bleeding disorders.