Noninvasive intermittent positive pressure ventilatory assistance/support (NIV) can permit long-term survival for patients with no autonomous ability to breathe. Its role was explored in the perioperative management of children with flaccid neuromuscular scoliosis. Vital capacity (VC), peak cough flow, and the extent of ventilator dependence were documented before and after surgical correction of scoliosis for children with Duchenne muscular dystrophy (DMD) and spinal muscular atrophy (SMA) with VCs as low as 2%. All patients and their caretakers were trained in NIV and mechanically assisted coughing preoperatively. Postoperatively, all were extubated using a specific protocol irrespective of their extent of ventilator dependence. Thirty-four children (16 DMD, 18 SMA) underwent posterior spinal arthrodesis for scoliosis at 11.7 (range, 6.6 to 16.6 y) years of age. The Cobb angle decreased from a mean 66 (range, 20 to 135 degrees) to 16 (range, 10 to 51 degrees) degrees. Fifteen patients (5 DMD, 10 SMA) had preoperative VC<40% of normal. All were extubated successfully by postoperative day 3 despite 14 failing preextubation and postextubation spontaneous breathing trials and requiring continuous NIV for up to 21 days after extubation. None had postoperative respiratory complications or required reintubation or readmission for pulmonary issues for at least 6 months postoperatively. Noninvasive positive pressure ventilator support is an alternative to invasive airway intubation in the perioperative management of children with flaccid neuromuscular scoliosis. Level IV-case series.