This clinical practice guideline addresses six clinical questions:1.Should hospitalized patients with cancer receive anticoagulation for VTE prophylaxis?2.Should ambulatory patients with cancer receive anticoagulation for VTE prophylaxis during sys- temic chemotherapy?3.Should patients with cancer undergoing surgery receive perioperative VTE prophylaxis?4.What is the best method for treatment of pa- tients with cancer with established VTE to prevent recurrence?