UFC 15 featured a Superfight between Randy Couture and Vitor Belfort, a Heavyweight Tournament, and two alternate bouts. The show also marked the last event to feature Bruce Beck, who had been the main play-by-play announcer starting with UFC 4. He was replaced by Mike Goldberg in UFC 16. This was the first Pay-per-view UFC event to feature a second referee, Joe Hamilton, who handled the less significant matches while "Big" John McCarthy still handled all the title and championship matches.
Collision Course marked a major change in the UFC's rules, with limitations set on permissible striking areas. Headbutts, groin strikes, strikes to the back of the neck & head, kicks to a downed opponent, small joint manipulation, and hair pulling all became officially illegal.