Current concepts of the many complex pathophysiological mechanisms and clinical and laboratory manifestations of disseminated intravascular coagulation (DIC) are presented. Considerable attention has been devoted to interrelationships within the hemostasis system. Only by clearly understanding these extraordinarily complex pathophysiological interrelationships can the clinician and laboratory scientist appreciate the divergent and wide spectrum of often confusing clinical and laboratory findings in patients with DIC. Many therapeutic decisions are controversial and will remain so until more is published about specific therapeutic modalities and survival patterns. The future holds promise for not only newer antithrombotic agents, but also agents which will block, blunt or modify cytokine activity and the activity of vasoactive substances. Also, therapy must be highly individualized depending on the nature of DIC, age, etiology of DIC, site and severity of hemorrhage or thrombosis and hemodynamic and other clinical parameters.