Malignancy is associated with a "hypercoagulable" state and a high risk for thrombohemorrhagic complications. Clinical complications may range from localized thrombosis to bleeding of varying degrees of severity because of disseminated intravascular coagulation (DIC). Life-threatening bleeding is frequent in acute leukemias, particularly in acute promyelocytic leukemia (APL). Laboratory assessments show profound hemostatic imbalance in this condition, with activation of coagulation, fibrinolysis, and nonspecific proteolysis systems. An important pathogenetic role is attributed to the leukemic cell properties interfering with the hemostatic mechanisms. However, chemotherapy and intercurrent infections also contribute to the bleeding risk in the patient with leukemia. In this article, we will attempt to describe what is currently known about the coagulopathy of acute leukemia, summarize the various aspects of the hemostatic abnormalities underlying this disorder, and revise the principal pathogenetic mechanisms. We will also try to provide information on the current therapeutic tools and recommendations for the management of life-threatening bleeding in this disease. Finally, a special focus will be devoted to the management of this complication in the era of all-trans retinoic acid (ATRA), a drug now indispensable in curing APL that has completely changed the natural history of APL and its coagulation/bleeding syndrome.