Noninvasive ventilation (NIV) has gained increasing acceptance over the years to reduce endotracheal intubation, pneumonia and to prevent or treat respiratory failure in patients with different diagnoses. The international consensus conference, and the British society guidelines on NIV ventilation have analyzed its use during the weaning phase concluding that there were still conflicting results of its use. However, recent clinical trials have shown clear clinical benefits on the use of NIV in several patient populations during the weaning period. Acute respiratory failure (ARF) during the weaning process is the main object of recently published studies. The latest published randomized trials on the application of NIV for acute respiratory failure following extubation failed to demonstrate any favorable outcome. Even so, the use of NIV during the process of weaning in patients experiencing multiple weaning failure or as a preventive therapy in patients at higher risk of respiratory deterioration showed improved clinical outcomes only in chronic obstructive pulmonary disease and in particular in hypercapnic patients. Reduced invasive mechanical ventilation, tracheostomy and lower mortality rate at 90 days were the major advantages.