As part of a major drive for excellence in basic research in the new millennium, the Chinese Academy of Sciences founded the Institute of Neuroscience (ION) on November 27^th, 1999. The institute is devoted to research in all areas of basic neuroscience, including molecular, cellular and developmental neurobiology, systems and computational neuroscience, as well as cognitive and behavioral neuroscience. At its inception, the Institute aims to establish the infrastructure of a modern research institute that provides an environment for rigorous scientific pursuit and fruitful interactions, a merit-based system for promotion and funding, and a high-quality training program for graduate students and postdoctoral fellows.  　　  

　　On November 27^th, 2019, a symposium on frontiers of neuroscience was held at the “320 campus” in honor of the 20^th anniversary of ION. ION alumni from around the country and abroad, as well as current ION members, attended the symposium and enjoyed this reunion. 

　　Prof. Muming Poo, the founding and current director of ION, addressed a speech during the symposium, reviewing ION’s development in the past 20 years, looking into the future of ION, sharing his opinion of the 8 key questions to be solved on neuroscience research.  

　　Profs. Aike Guo (ION), Xu Zhang (ION), Shumin Duan (Zhejiang University, former PI of ION), Zhuan Zhou (Peking University, former PI of ION), Hailan Hu (Zhejiang University, former PI of ION) and Yousheng Shu (Beijing Normal University, former PI of ION) gave talks on their research findings. 

　　During the past 20 years, 433 students graduated from ION and 78 of them became PIs and started their own scientific careers. 14 PIs who graduated from ION returned to the campus and also gave talks on their recent progress this time.  

　　Profs. Shumin Duan and Tianle Xu, on behalf of all the PI alumni, gave a replica of Da Ke Ding and a colored-glaze craft in monkey shape to ION, in celebrating ION 20^th anniversary. Da Ke Ding is a bronze food vessel from western Zhou and a very impressive collection in Shanghai Museum. Da Ke Ding represents the best wishes from the PI alumni, as Ding’s pronunciation is the same as the Chinese words “top” or “best”. 

　　Prof. Yichang Jia, on behalf of all the student alumni, gave the specially designed mugs to ION, in the meaning of “喝水不忘挖井人”.