Williams officiates in the Asian Champions League (ACL),[1] AFC Cup and in the Australian A-League football competition.

[2] He was selected to officiate at the 2012 Asian Champions League (ACL) final in Korea between Ulsan Hyundai and Al Ahli.

[4] He officiated in the opening Great Britain match at Old Trafford against Senegal in front of approximately 75,000 spectators.

He refereed his 100th[7] match, Central Coast Mariners vs Adelaide United, at Bluetongue Stadium in March 2012.

In 2020 he was promoted to an executive position at the University of Canberra High School Kaleen where he continues to teach physical education.