In this comprehensive review, coagulopathy and its relevance to emergency medical services will be presented. Common pathophysiology that causes bleeding disorders will be explained in the context of case studies. A review of common anticoagulants and medications that induce coagulopathy will be presented in the context of these pathophysiologic mechanisms. Laboratory values relevant to each mechanism and medication will be discussed so that attendees gain further insight into treatment of clotting disorders. Finally, an overview of the current literature surrounding whole blood transfusion and the different components of blood products will be presented, especially as they relate to trauma resuscitation.'