OBJECTIVE. The purpose of our study was to evaluate the usefulness of venous flow augmentation with duplex sonography in the evaluation of deep venous thrombus of the lower extremities. CONCLUSION. The augmentation component of the lower extremity sonogram rarely provides additional information in the diagnosis of deep venous thrombus. In our large series, no deep venous thromboses were discovered with augmentation. Factors such as the lack of usefulness and patient discomfort may justify removal of augmentation from the routine study. However, augmentation should still be applied as a diagnostic tool in difficult or uncertain cases. © American Roentgen Ray Society.