Patients presenting to the emergency department with acute bleeding and a history of clotting or platelet disorder present a unique challenge to the emergency physician. The severity of bleeding presentation is based on mechanism as well as factor levels: patients with factor levels greater than 5% can respond to most minor hemostatic challenges, whereas those with factor levels less than 1% bleed with minor trauma or even spontaneously. Treatment should be initiated in consultation with the patient's hematologist using medications and specific factor replacement, except in rare, life-threatening, resource-poor situations, when cryoprecipitate or activated prothrombin complex may be considerations.