UFC 21: Return of the Champions was a mixed martial arts event held by the Ultimate Fighting Championship on July 16, 1999 at the Five Seasons Events Center in Cedar Rapids, Iowa. The event was seen live on pay per view in the United States, and later released on home video.

UFC 22: Only One Can be Champion was a mixed martial arts event held by the Ultimate Fighting Championship on September 24, 1999 at the Lake Charles Civic Center in Lake Charles, Louisiana.