Prof. Hwang Hyeon-shik in the Dept. of Orthodontics, College of Dentistry, delivered a special lecture at the 104th annual session of the American Association of Orthodontics (AAO) with many world-renowned orthodontists attending. For the Doctors’ Scientific Program of AAO’s 104th session, held in Orlando, Florida, USA from April 30 through May 4, Prof. Hwang delivered a lecture on ‘Precision Diagnosis of Facial Asymmetry.’ As director of the Korean Adult Orthodontic Research Institute, Prof. Hwang’s research interest lies in adult orthodontic treatment. With the increase in demand of facial esthetics, the need of accurate diagnosis of facial asymmetry is increasing in orthodontic practice. Some patients complain of the development or progression of facial asymmetry during or after orthodontic treatment. While most orthodontists take postero-anterior (PA) cephalograms for the purpose of evaluating facial asymmetry, they have many limitations. In his presentation, Prof. Hwang discussed the limitations of PA cephalometric radiography and provided possible solutions on the basis of clinical results. Since 1995, when he was invited by AAO to give a special lecture for the first time, this is the third time for him to give a lecture at AAO. He is the first Korean scholar who was invited to give a special lecture at the meetings of AAO. In addition, he has participated in international conferences such as Indian Association of Orthodontics and Asia-Pacific Association of Orthodontics to give keynote speeches or special lectures. On March 28, Prof. Hwang presented the results of facial asymmetry studies at the Dental Hospital of Seoul National University. His presentation lasted for the whole day.