Continuous positive airway pressure is the gold standard for treatment of obstructive sleep apnea. For certain conditions, such as central sleep apnea, hypoventilation, hypercapnic respiratory failure, and restrictive lung disease, noninvasive ventilation (NIV), which includes respiratory assist devices and home mechanical ventilators, may be indicated. This article will review the various positive airway pressure and NIV devices currently available as well as the modes, settings, indications, and contraindications of these devices in both the inpatient and outpatient settings. Additional device features, accessories, troubleshooting, and insurance guidelines will also be discussed.