Patients undergoing elective hip and knee replacement require some form of prophylaxis to minimize the risk of deep vein thrombosis and pulmonary embolism, which is the most immediate risk to their life after this procedure. The American College of Chest Physicians (ACCP) has recommended various types of prophylaxis based on review of large-scale randomized studies that used venography as an endpoint. Many orthopedic surgeons consider the grade 1A recommendations of the ACCP aggressive anticoagulation by orthopedic standards. A number of orthopedic studies have recently shown that there are more complications associated with such aggressive protocols than have been previously reported. In response to this, the American Academy of Orthopaedic Surgeons formed a workforce that recently issued recommendations based on prevention of symptomatic thromboembolic events rather than just the results of venography. The recommendations resulting from this workforce give orthopedic surgeons more latitude in selecting less aggressive protocols with the aim of an equal level of efficacy while reducing the complications associated with aggressive thromboprophylaxis protocols.