[2] His father is a former lecturer in geology at the Australian National University and his mother is a former English teacher at Canberra High School.
He played for the Australian Schoolboys rugby union team, and was the sprint champion of Combined Associated Schools.
[3] Williams debuted for the Wallabies in the 1984 tour of the British Isles, where originally he was not part of the Australian squad, but was called up as replacement after Brendan Moon injured an arm during the match against England.
Williams also played in The Varsity Match for Oxford University, which he also attended before finishing his studies.
Later, he moved to Japan, where he played for Kobe Steel, where he was part of the squad of the club's golden age.