Prof. Chnag Wan Oh, the President of Korean Neurosurgical Society kindly invited me as a guest speaker to the 38th. Spring Annual Meeting of Korean Neurosurgical Society on July 31 – Aug 1, which was their first on-line meeting because of COVID-19 pandemic. In this virtual meeting, I could have an opportunity to give a lecture on moyamoya disease, entitled “Recent Advances in Diagnosis and Bypass Surgery for Moyamoya Disease”. Prof. Oh kindly let me know that my lecture video had registered 2,005 views by the 1,450 registered members. I am very happy and honored to contribute to them through the on-line meeting this time.