The use of HFOV in adults is still in its infancy. There is, however, much promise to support further study of this ventilatory modality. Rescue case series have shown that HFOV is effective in improving gas exchange and appears safe in this group of extremely ill patients. In addition, as evidence continues to mount regarding the importance of VILI and its mechanisms, HFOV provides a theoretically attractive alternative to conventional lung-protective ventilatory modes. When HFOV is used in adults, it should be in conjunction with an effort to recruit atelectatic lung units by employing higher mean airway pressures and weaning FIO2 before P(AW). HFOV could be used as one of a number of new therapies for the patient failing to oxygenate on CMV. Its routine use to prevent VILI cannot be recommended at this time, as no data are available. Further clinical studies potentially leading to a large randomized controlled trial of HFOV versus best conventional therapy appear worth pursuing.