The Dong-a Ilbo
The Guksu is a Go competition held by the Hanguk Kiwon, and sponsored by The Dong-a Ilbo. It is the longest running competition in South Korea. Even though it is no longer the largest tournament in terms of prize money, many people still consider the Guksu title (Guksu literally means "hand of the nation" or the best player in the country) to be the most prestigious of all Korean titles, especially given its long tradition.