This document summarizes evidence on the use of noninvasive ventilation (NIV) in acute respiratory failure. It finds that NIV is an effective first-line treatment for moderate-to-severe exacerbations of chronic obstructive pulmonary disease (COPD) and acute cardiogenic pulmonary edema, reducing the need for invasive mechanical ventilation and improving outcomes. It also discusses how NIV is used in other clinical settings such as postoperative care, pneumonia, asthma, and palliative care. The document concludes that appropriate patient selection and technique are important for the successful use of NIV.