A description of the continued experience acquired by transfusion of cryoprecipitates respectively 2 and 3 times a week in the prophylactic treatment of 2 young patients with hemophilia A now extending over periods of almost 3 years and more than 2½ years. The conclusion that with 3 transfusions per week of one cryoprecipitate, equivalent to 900–1,500 U of AHF weekly, effective prophylaxis of joint hemorrhages is achieved in these patients, seems justified. During these periods hospital admissions were reduced to a few only, and were with one exception on account of a trauma. Radiologically the changes in the joints already existing before prophylactic treatment was started, showed practically no progression