Endoscopic sinus surgery is a surgical methodology within the field of otolaryngology that utilizes endoscopic visualization to access and treat pathologies of the paranasal sinuses, primarily aiming to restore physiological ventilation and mucociliary clearance. As a research concept and clinical practice, it encompasses the systematic investigation of optimal surgical techniques, instrumentation, indications, patient selection criteria, and long-term outcomes for various sinonasal conditions, including chronic rhinosinusitis and nasal polyposis. Its significance lies in establishing a minimally invasive paradigm that has fundamentally transformed the management of complex sinus disease, demonstrating enhanced efficacy and reduced morbidity compared to traditional surgical approaches.