To provide an updated overview of the complex coagulopathy associated with malignancy, together with the advances in our knowledge of the interactions of cancer with the hemostatic system. Also, to offer an update of the recent progresses in the risk assessment, prevention, and treatment of thrombohemorrhagic complications in cancer patients. Mechanisms underlying the hemostatic derangement caused by cancer include many prothrombotic properties of tumor tissues. Of extreme interest are the most recent findings that the regulation of tumor cell hemostatic protein expression is driven by oncogenes, the tumor-derived tissue factor-positive microparticles are an important player in thrombosis, and the changes in the tumor microenvironment in the presence of tissue factor affect 'dormant' cells to shift to a malignant phenotype.On the clinical side, risk assessment models, based on clinical and biological risk factors, are becoming very attractive to identify categories of cancer patients at different thrombotic risk. Unsuspected pulmonary embolism, incidentally discovered, is also opening an intensive area of research. Finally, new updates of the guidelines to help clinicians in the management of venous thromboembolism in cancer patient have been recently released. The coagulopathy of cancer is complex. Thrombotic and bleeding complications significantly contribute to morbidity and mortality in this disease. The accrued knowledge of the underlying mechanisms is helping establish more accurate and appropriate interventions for the management of the thrombotic risk in these patients.