Anticoagulant therapy is challenging to modern surgical practice because it complicates risks of bleeding and the need for allogeneic blood transfusions. In an aging population, there is extensive use of antiplatelet agents, and patients present for operations receiving these agents. Hemostatic inhibitors are reviewed here, including anticoagulants, platelet inhibitors (clopidogrel), low-molecular-weight heparins, pentasaccharide (fondaparinux), and other factor Xa inhibitors. Agents used to manage bleeding, including aprotinin, lysine analogs, desmopressin, and recombinant factor VIIa, are discussed.