Biu Tze by GM Leung Ting is the third and most advanced set in the Wing Tsun system. In the past, we had a saying, "Biu Tze does not leave the door," meaning that those Wing Tsun (Wing Chun) practitioners who did not attain a certain level of skill could not even have seen the set, let alone hope to learn it. This is because senior disciples who understood this set would absolutely not practice it in front of their regular younger kung fu brothers. Thus, one can appreciate the great regard in which our forebears held this set.