is performed on the human larynx to treat phonatory dysfunction and improve the quality of voice. 2. There are two major categories of phonosurgery. One surgical option is open-neck laryngeal surgery, which is performed via an extralaryngeal approach. The other is endolaryngeal microsurgery and endoscopic surgery, which are performed via an intralaryngeal approach. 3. When performing phonosurgery via an extralaryngeal approach, it is very important to be able to visualize the internal laryngeal structures by looking at the laryngeal cartilage. Furthermore, when performing phonosurgery via an intralaryngeal approach, it is important to be able to visualize the internal laryngeal structures, including histoanatomy, by observing the mucosa of the lumen. An understanding of the histologic structures of the vocal fold is also essential when performing phonosurgery. 4. Knowledge of the three-dimensional structure, histology and histopathology of the larynx is indispensable when performing phonosurgery.