The prescription of continuous positive airway pressure (CPAP) for patients with obstructive sleep apnea (OSA) is increasing globally; thus CPAP adherence becomes the next major issue for OSA therapy. Advanced CPAP should be admitted as a high-flow generator device to maintain constant upper airway pressure through an expiratory port following variable spontaneous respiratory swings. It is not a simple pump device. Recently, dynamic respiratory events under CPAP therapy can be detected and recorded by assessing CPAP inspiratory flow. The pathogenesis of obstructive sleep apnea is a passive upper airway collapse during sleep. Before occurring the upper airway collapse, the narrowing upper airway induces acute flow limitation during inspiration. To keep the patency of the upper airway, the latest Auto CPAP device eliminates acute inspiratory flow limitation by increasing CPAP flow and pressure before obstructive events. To evaluate CPAP adherence and manage CPAP problems, physicians have to understand the basic mechanics of advanced CPAP device. It is required that standardized CPAP care manual with scientific evidence-based troubleshooting.