Hemostasis in the operating theatre has always been an issue of fundamental importance in any surgical procedure. The amount of blood loss may greatly vary between different surgical procedures and depends on both surgical and non-surgical factors. Several different topical agents can be used to achieve or maintain hemostasis in surgical patients. Hemostatic agents can be divided into two categories: those that provide their mechanism of action on the clotting cascade in a biologically active manner (active agents) and those that act passively through contact activation and promotion of platelet aggregation (passive agents). These products are available in a wide range of devices and are nowadays accepted and extensively used in the vast majority of surgical specialties with appreciable results in terms of blood loss sparing.