AbstractThe process of crossmatching blood is an integral part of blood bank operations. Human blood is specialized in the sense that one person's donated blood cannot be used randomly for another person. Before blood is infused to a patient, a test is performed to determine if the patient's blood matches the blood to be infused. Only blood that matches the patient's blood is acceptable. Two blood crossmatch policies are compared. The commonly used policy is compared to a modified policy and it is found that the latter can produce considerable savings in blood and concomitant costs. The absorbing Markov chain model is used to evaluate the two crossmatch policies.