Based on recent analyses of randomized trials suggesting that continuous positive airway pressure (CPAP) treatment of obstructive sleep apnea (OSA) is associated with weight gain, this multidisciplinary symposium brings together experts from obesity, behavioral, pulmonary and sleep medicine fields to address essential questions: What could be the underlying mechanisms for weight gain after CPAP, including its impact on energy expenditure, food intake, and physical activity? What is the clinical significance of the weight gain after CPAP? How does CPAP affect body composition? What are novel, technology-based weight loss interventions to mitigate weight gain in OSA management?