Noninvasive positive pressure ventilation (NPPV) is becoming more commonplace, both in the ICU and also in the Emergency Department. This article addresses the rationale and mechanism of action for NPPV. A review of the indications for using NPPV and a discussion detailing the initiation of NPPV follows. NPPV has been shown to decrease length of hospital stay and the need for intubation in patients who have chronic obstructive pulmonary disease and acute cardiogenic pulmonary edema. NPPV should be considered for most patients who have respiratory distress who are being considered for intubation. After NPPV is initiated, very close monitoring and follow-up must be employed to identify those patients who are at risk for treatment failure.