Venous thromboembolism (VTE) is a common complication in patients with malignant disease. Its management remains challenging because patients with a cancer-associated thrombosis are at higher risk of recurrent VTE than are noncancer subjects with thrombosis and also have a greater risk for anticoagulant-associated bleeding complications while receiving therapy to prevent recurrent VTE. Recently, anticoagulant strategies based on the administration of low-molecular-weight heparin (LMWH) rather than vitamin K antagonists for up to 6 days to prevent recurrent VTE have been evaluated. These studies indicate that LMWH is associated with a lower rate for recurrent VTE and similar rates of bleeding when compared with oral anticoagulant therapy. Chronic exposure to LMWH may also prolong survival of cancer patients.