Drug-Induced Sedation Endoscopy (DISE) consists of the direct observation of the upper airways during sedative-induced sleep, allowing the identification of the sites of pharyngeal collapse, which is the main pathological event in Obstructive Sleep Apnea (OSA). The Authors have compared Target Controlled Infusion (TCI) sedation endoscopy (TCI-DISE) technique to conventional DISE (CDISE), performed by a manual bolus injection of sedative agent, to recreate accurately and safely snoring and apnea patterns comparable to natural sleep. The authors conducted a prospective, randomized, long-term study and a retrospective analysis of surgical outcomes. The apnea-event observation and its correlation with pharyngeal collapse patterns is the primary endpoint; secondary endpoints are defined as stability and safety of sedation plan of DISE-TCI technique. From January 2009 to January 2011, OSA patients were included in the study and randomly allocated into two groups: the bolus injection conventional DISE group and the TCI-DISE group. Third endpoint is to compare the surgical outcomes enrolling OSA patients from January 2009 to June 2015. We recorded the complete apnea-event at oropharynx and hypopharynx levels in 15/50 pts in conventional DISE group (30%) and in 99/123 pts in TCI-DISE group (81%) (p < 0.0001). Four pts needed oxygen in conventional DISE group because a severe desaturation occurred during the first bolus of propofol (1 mg/kg) (p = 0.4872 ns). We recorded instability of the sedation plan in 13 patients of conventional DISE group (65%) and 1 patient of the TCI-DISE group (5%) (p = 0.0001). In 37 TCI-DISE group surgical patients we reported a significant reduction of postoperative AHI (from 42.7 ± 20.2 to 11.4 ± 10.3) in comparison with postoperative AHI in 15 C-DISE group surgical patients (from 41.3 ± 23.4 to 20.4 ± 15.5) (p = 0.05). Our results suggest the DISE-TCI technique as first choice in performing sleep-endoscopy because of its increased accuracy, stability and safety. However, it is mandatory an accurate assessment of PSG/PM, which allows us to differentiate OSA patients in whom UA anatomical abnormalities are predominant in comparison with not-anatomical pathophysiologic factors, achieving good surgical patient’s selection and outcomes as a consequence.