Who is the master of the Tae Kwon Do chang moo kwan?

Yoon Byung In was the original founder. However when he disappeared during the Korean War his student Lee Nam Suk carried out his teachings.

For many years Kim Soon Bae was the head of the Chang Moo Kwan. However, recently he's been very ill and is quite old so the current head of Chang Moo Kwan in Korea (the World Taekwondo Changmookwan Federation) is Kim Joong Young.