Sleep-related breathing disorders are complex problems. OSA is one of the major sleep problems not only in elderly but also in the younger patients. It is associated with marked comorbidity and mortality. Till now, mainstay of treatment for OSA is CPAP which is noted for poor compliance in most of the patients. Sleep endoscopy is one of the studies to know the obstruction site in the OSA patients. With precise site, the treatment of the OSA can be individualized and personalized.