H. Donald Buck is the first official black belt member of the National
Headquarters in the United States.
He studied under Hanshi
Gogen Yamaguchi (the founder of Goju-Kai Karate-Do institution) and his
sons Hanshi Gosei Yamaguchi, his first son Hanshi Gosen Yamaguchi, the
second son and Hanshi Goshi Yamaguchi, the third son.
Shihan H. Donald Buck
obtained his rank of black belt, in March 1964 and currently holds Roku-Dan,
or 6th Degree rank of black belt, which is the highest rank given to
practitioners in the U.S..