Mechanical measures such as graduated compression stockings and intermittent compression boots are available for venous thrombosis prophylaxis, but compliance may be limited. Plantar venous pneumatic compression devices have attained widespread acceptance by both patients and nurses because of their comfort and compact size, but their track record for efficacy is poor. Inferior vena cava filters prevent pulmonary embolism, but do not halt the thrombotic process or prevent venous thrombosis. Pharmacologic prophylaxis traditionally has relied upon minidose unfractionated heparin; however, re-examination is warranted in the face of increasingly ill and complex patients. My opinion is that small, fixed doses of once-daily low molecular weight heparin will eventually replace minidose unfractionated heparin as the standard pharmacologic prophylaxis regimen for most surgical and medical patients. Prolongation of prophylaxis after hospital discharge should receive increased emphasis. Most patients being transferred to a skilled nursing facility should receive venous thromboembolism prophylaxis. Similarly, most patients undergoing total hip or knee replacement should receive prolonged preventive regimens, with at least 1 month of anticoagulation. Despite advances, certain aspects of venous thrombosis prophylaxis remain problematic. First, a surprisingly high number of hospitalized patients develop venous thrombosis because of failed (rather than omitted) prophylaxis. Second, many patients in intensive care have a combination of peripheral vascular disease and active bleeding (usually gastrointestinal) that precludes mechanical or pharmacologic prophylaxis. Third, neurosurgical patients undergoing craniotomy for brain tumors suffer a high rate of venous thrombosis and major pulmonary embolism despite the routine use of combined mechanical and pharmacologic prophylaxis. My opinion is that these three areas, in addition to the hospital culture of prophylaxis, should receive increased attention in an effort to prevent venous thromboembolism.