Early career Weber began his coaching career with a brief stint as a graduate assistant coach at
Western Kentucky University during the 1979–80 season under head coach
Gene Keady. In 1980, Weber moved to
Purdue University along with Keady. He remained an assistant coach at Purdue for 18 seasons before becoming the head coach at
Southern Illinois University in 1998.
Southern Illinois In his five seasons at Southern Illinois, Weber led the Salukis to consecutive
Missouri Valley Conference championships and
NCAA tournament appearances in
2002 and
2003, including a
Sweet Sixteen finish in 2002.
University of Illinois On April 30, 2003, Weber was hired by
Illinois to replace
Bill Self, who had departed from Illinois to take the head coaching job at
Kansas.
2003–04 season The Illini played a tough early season game against
North Carolina on December 2 in Greensboro, and were tied at 69 with just six minutes to go. Illinois eventually lost the game 88–81, but it proved to be a good test for the young team with no seniors in the starting lineup. Weber faced his toughest test after starting the conference schedule with an even 3–3 mark. He changed many doubters' minds by winning the remaining ten games on the conference schedule, winning the
Big Ten title outright for the first time since 1952. The Illini finished second losing to
Wisconsin in the
Big Ten tournament championship game. They received a bid as a #5 seed in the
2004 NCAA tournament, defeating
Murray State and
Cincinnati in the first two rounds to reach the Sweet Sixteen. A 72–62 loss to top-seeded
Duke ended their tournament run, but capped a solid first season for coach Weber.
2004–05 season The 2005 season opened with high expectations and the return of all the team's starters. On December 1, the Illini defeated the number-one ranked team,
Wake Forest, 91–73, at
Assembly Hall. Weber sported a glowing orange blazer for the game, and Assembly Hall was painted orange by the 16,618 fans wearing school colors. The pressure grew for Weber as the victory vaulted the Illini to the top spot in the polls the following week, a spot they would carry for the rest of the season. Regular season perfection and their 29–0 record ended on the last game of the regular season, however, as Illinois lost a 12-point, second half lead to
Ohio State and lost on a last second shot to the
Thad Matta-coached Buckeyes, 65–64. The Illini won the Big Ten regular season and
Tournament titles. In the
2005 NCAA tournament the team received the overall #1 seed, and top seed in the Midwest Regional. Illinois defeated
Fairleigh Dickinson and
Nevada in the first two rounds in
Indianapolis. In the Sweet Sixteen, Weber led the Illini to a victory over his alma-mater,
Milwaukee, then defeated
Arizona in an amazing comeback to advance to the Final Four. After leading Illinois to a win over
Louisville in the Final Four, Weber could not deliver the Fighting Illini their first national championship, falling 75–70 to
North Carolina in the
National Championship game. Weber coached the team to the best record in school history, finishing 37–2, and tying the NCAA record for most wins in a season. Weber won many coaching awards after the season, including the
Naismith Award and the
Henry Iba Award.
2005–2012 Despite losing three starters, including two to the
NBA, the Illini finished the
2005–06 season with a 26–7 record and reached the second round of the
NCAA tournament. The
2006–07 season had a disappointing start, including the first three-game losing streak in Weber's tenure. However, the Illini rebounded to finish 23–11 and again qualify for the
NCAA tournament. The
2007–08 season marked the first time during Weber's tenure that the Illini did not qualify for a postseason tournament, finishing the season with an overall record of 16–19, 5–13 in the
Big Ten. The team improved markedly the
following year, however, finishing 24–10, 11–7 in the
Big Ten and returning to
NCAA tournament. After a 10–0 start to the
2011–12 season, Weber's Illini went 7–15, finishing the season with a 17–15 record. On March 9, 2012, one day after the Illini lost its
Big Ten tournament opening-round game to Iowa, Weber was relieved of his duties. During his nine-year tenure as Illinois coach, Weber amassed a Big Ten record of 89–64, and an overall record of 210–101. At the time of his firing, his overall win percentage with Illinois (67.5%) stood as second only to Bill Self in the modern era and his 210 wins were the third-most in school history, behind only
Lou Henson and
Harry Combes.
Kansas State University On March 31, 2012, Weber was hired as head coach at
Kansas State University, replacing
Frank Martin, who had departed to become head coach at
South Carolina. In his
first season at K-State, Weber led the Wildcats to 27–8 record and tied for the
Big 12 Conference title with a 14–4 conference mark. The title was K-State's first regular-season conference championship since 1977. Weber was named the 2013
Big 12 Conference Men's Basketball Coach of the Year. His first season at KSU ended with an upset loss in the second round of the
NCAA tournament to
LaSalle, 63–61, in Kansas City's
Sprint Center. The team finished ranked #12 in the nation in the AP Poll and #20 in the Coaches Poll. Senior
Rodney McGruder was named first-team all-conference. Shortly after the end of Weber's first season, starting point guard
Ángel Rodríguez and two other players announced their intentions to transfer. Kansas State's roster was further thinned when incoming freshman Neville Fincher was declared ineligible for the
2013–14 season, and incoming point guard Jevon Thomas was declared ineligible for the fall semester. Weber started his second season at Kansas State 0–1, but finished the non-conference schedule with an 8-game winning streak and a 10–3 record. In its first conference game, Kansas State upset #6
Oklahoma State and earned a #25 ranking in the following week's
AP Poll. The team finished the regular season with a 20–12 record, 10–8 in the Big 12, and returned to the
NCAA tournament for a school-record fifth straight season. Weber's
third season at Kansas State ended with a 15–17 record (8–10 in Big 12 play), and the school did not advance to the NCAA Tournament for the first time since
2009. The losing record was only the second for Weber in his first 17 seasons as a head coach. Following the season, Weber's squad saw the transfer and departure of six scholarship players, including
Marcus Foster, Jevon Thomas, Nigel Johnson, Tre Harris and Malek Harris. The following season, Weber's Wildcats finished the
2015–16 season 17–15, 5–13 in
Big 12 play. In
2016–17, the Wildcats returned to the NCAA tournament and finished with a 21–14 (8–10) record. In
2017–18, the team improved to 25–12 (10–8) and advanced to the Elite Eight of the
2018 NCAA tournament, including a 61–58 win over
Kentucky in the Sweet Sixteen. The team received a #19 national ranking at season's end in the Coaches Poll. In
2018–19, the team tied with
Texas Tech for its second regular-season Big 12 Conference title under Weber, with a 14–4 conference record. For the third consecutive season, Kansas State was invited to the
NCAA tournament. After an upset first-round loss in the NCAA tournament, the team finished with a 25–9 record and a #18 national ranking in the AP Poll, and #19 ranking in the Coaches Poll. Two players from the team were named first-team all-conference:
Dean Wade and
Barry Brown Jr. After winning two conference titles and making five NCAA tournament appearances in his first seven seasons at KSU, Weber's final three teams posted losing records: 11–21 in
2020, 9–20 in
2021, and 14–17 in
2022. The day after a loss to
West Virginia in the
Big 12 tournament, Weber announced his resignation from Kansas State. Weber's tenure with Kansas State concluded with two conference co-championships and five NCAA Tournament appearances, including an appearance in the 2018 Elite Eight. At the time of his resignation, he ranked third on K-State's all-time total wins list, behind only
Jack Hartman and
Tex Winter, and 11th in overall winning percentage.
National team In the summer of 2019, Weber coached the
United States national under-19 team at the
2019 FIBA Under-19 World Cup in
Heraklion, Greece. His team won the tournament championship with a 7–0 record. ==Head coaching record==