Functional Endoscopic Sinus Surgery (FESS) has emerged as a cornerstone in the management of chronic and recurrent sinus diseases, offering a minimally invasive approach that preserves mucosal integrity and restores normal sinus ventilation. This review outlines the indications, surgical techniques, postoperative care, and complications associated with FESS. Emphasis is placed on the clinical benefits, the evolution of surgical steps, and the management of potential adverse outcomes. While FESS demonstrates high success rates in appropriate candidates, careful patient selection and surgical expertise remain essential to minimizing complications and ensuring optimal outcomes.