High-frequency ventilation, including HFJV, is an interesting alternative approach to mechanical ventilatory support that may offer benefits in terms of improved gas exchange and lower maximal alveolar distending pressures. Clinical data demonstrating improved outcome exist for neonatal and some forms of pediatric respiratory failure. No such data, however, exist for adults. Important complications can develop, and an extensive learning curve is required for operators to become skilled at delivering proper support safely. Presently, HFV should be limited to only specific applications (e.g., selected neonates, adult airway surgical procedures) and to centers skilled in its use. Considerably more data are required before extensive application, especially in the adult, is warranted.