Management of bleeding is an important part of any invasive procedure, and a wide variety of topical adjunctive hemostatic agents are available to supplement the surgeon’s application of conventional approaches to this critical outcome. To support the safe and effective use of these products, the perioperative nurse should have a thorough understanding of how they work and when they can be used appropriately. This course begins with a description of the components of whole blood and the natural process of hemostasis, followed by an explanation of where topical hemostats act within this sequence of events.