Ultrasonically activated devices (USADs) are a widely used alternative to suture ligation and clips in open and laparoscopic surgery because of their fast and easy control of bleeding without significant complications. By inducing protein denaturation and forming coaptive coagulation to seal vessels for cutting tissue, USADs result in reduced operating time, blood loss and hospital stay. Recently, various other types of vessel sealers have become available. In this article, we summarize the mechanism, efficacy and the advantages and disadvantages of USADs for appropriate use in surgery.