Junior Career:
In 1984, as a 16-year-old, Fleury joined the Moose Jaw Warriors of the WHL. In his second year he emerged as the team leader, and in his third and fourth years he became a star for his offensive achievements and for his entertaining, all-out style of play. In 1986 he played for Canada at the World Junior Championships in Czechoslovakia. Fleury brought his typical pesky game to the championships, but was involved in an infamous brawl that cost Canada a chance at the gold medal.

Fleury was a 9th round selection by the Calgary Flames in the 1987 NHL Entry Draft. He then played a final season in Moose Jaw in 1987-88, tying Swift Current's Joe Sakic for the league scoring title. He also racked up 235 minutes in penalties as he stepped up his aggressive play to combat the criticism of his size. He once again played in the World Junior Championships, this time as team captain in which Canada won the gold medal. Fleury was named to the tournament's All-Star team.

NHL Career:
Though Fleury was confident in his abilities, the Flames seemed less than sure. They signed him to a pro contract late in the 1987-88 season, just in time for him to join Salt Lake for the IHL playoffs. He seized the opportunity, scoring 11 goals in 8 games and lead the Golden Eagles to the Turner Cup championship. He began the next season in Salt Lake but an outburst of 37 goals and 74 points in only 40 games finally convinced the Flames that he deserved a chance to play in the NHL.

Used at center and at right wing, Fleury helped the Flames capture the Stanley Cup in 1989, and in his first full season he scored 31 goals. In 1990-91 he netted 51 goals and 104 points, and he made his first appearance at the NHL All-Star Game. Prior to the next season he played in the Canada Cup tournament, and he went on to score 30 or more goals in each of his next three seasons. He was also among the league leaders with 29 during the lockout-shortened 1994-95 season.

Team Leader:
Though outspoken and often brash, aggravating opponents, Fleury matured in time, becoming team captain in 1995. He continued to pick up honors for his hard work, including a berth on the league's Second All-Star Team in 1995 and spots on Team Canada's roster at the 1996 World Cup of Hockey, the 1998 Nagano Olympics and later down the road Canada's Gold Medal Olympic Team in Salt Lake City. On November 29, 1997, Fleury scored his 315th career goal, passing Joe Nieuwendyk for first place on the Flames' all-time list.

Free Agent:
In February 1999 the Flames, who felt they wouldn't be able to re-sign Fleury when his contract expired that summer, traded him to the Colorado Avalanche. He ended up with a season total of 40 goals and then signed as a free agent with the New York Rangers during the off-season. He went on to play three seasons on Broadway before joining the Chicago Blackhawks for one season in 2002-03. In October, 2002 Fleury was suspended indefinitely by the NHL for violating terms of his substance abuse aftercare program; then reinstated and cleared to return to active duty in December; then suspended again indefinitely in April, 2003.

Post NHL:

• 2005 - In an attempt to restore his career, Fleury acquired his NHL release and played for the "Horse Lake Thunder" competing for the Allan Cup in Lloydminster, Alberta.
• Signed as a free agent by Belfast (Britain), August, 2005 and played for one season in the British Elite Ice Hockey League. He was voted "Elite League Player OF The Year."
• Reality Television:
  Fleury resides in Calgary, and currently operates Fleury's Concrete Coatings, a successful concrete sealing business he started with his wife Jennifer and brother Travis. They filmed a pilot episode in 2007 for a reality TV series based around his concrete business called Theoren Fleury: Rock Solid. "We want to show people that if you have a dream, anything is possible with a little ambition," Fleury said of the premise of the series.
  
• Calgary Vipers:
  Fleury launched a line of clothing called "FAKE" (Fleury's Artistic Kustom Enterprises) in 2008, and approached the Calgary Vipers of the independent Golden Baseball League hoping to convince the team to use his brand of practice jersies. The conversation led to talk of Fleury suiting up in a game for the Vipers. On August 9, 2008, Fleury made his professional baseball debut at the age of 40, hitting a single in a pinch-hit appearance against the Yuma Scorpions in the first game of a doubleheader. Fleury started the second game at left field, striking out twice before he was replaced. "I've had so many things happen in my life already that I sometimes surprise myself with the things I've done, the things I've accomplished. This was just another one of those days," Fleury said of his appearance with the Vipers.
• Autobiography:
  Fleury is working on his autobiography with writer Kirstie Mclellan Day, working title: "Driven by the Devil" will be published fall 2009 by Harper Collins in Canada and Triumph Books in the USA according to Avenue Magazine, Calgary edition, October 2008 and denverpost.com.

Awards:
WHL East First All-Star Team (1987)
WJC-A All-Star Team (1988)
WHL East Second All-Star Team (1988)
Shared Alka-Seltzer Plus Award with Marty McSorley (1991)
NHL Second All-Star Team (1995) Played in NHL All-Star Game (1991, 1992, 1996, 1997, 1998, 1999, 2001)