Recombinant factor VIII is currently in the late stages of clinical trials. The available studies indicate that the product is safe and well-tolerated, and appears to be free of virus diseases such as HIV and hepatitis infections. Based on these early studies, recombinant coagulation factors appear to have enormous promise and potential for transfusion medicine. The synthesis of large quantities of safe material may lead to the development of techniques for daily administration of factor VIII aimed at the prevention of joint and soft tissue bleedings. There is also the promise of decreased costs, as techniques for the efficient synthesis of recombinant proteins are refined further.