Some criteria have been suggested to predict early and more accurately the moment the patient is ready to be separated from the ventilator. At the present time, the f/VT ratio (rapid shallow breathing index) appears to yield the best predictive power. All methods of weaning have their advantages and disadvantages, and the method of weaning per se’ is not the only critical factor. And the conclusions were different regarding the best method of weaning. New computer-assisted systems already are tested and, in the future, may provide a significant advantage in the management of weaning from mechanical ventilation.