Henson began his coaching career at Las Cruces High School in Las Cruces, New Mexico in 1956. After two years as junior varsity coach, Henson was head coach of the varsity team from 1958 to 1962 and won state championships in 1959, 1960, and 1961. He started coaching in the college ranks in 1962 at Hardin-Simmons University. As a condition of taking the Hardin-Simmons job, Henson insisted that the team be racially integrated, a condition to which the university agreed. In 1966, he took over at his alma mater, New Mexico State University. In his first season at NMSU, the Aggies rebounded from a 4–22 record in the prior season to finish 15–11 and went to the NCAA Tournament. In 1970, Henson would help lead the Aggies to the Final Four for the only time in the school's history. Henson and future NBA players Jimmy Collins, Sam Lacey, and Charlie Criss lost in the tournament semifinal to eventual champion UCLA, the third time in three years the Aggies lost to UCLA in the tournament. Henson coached at New Mexico State for nine seasons, with six trips to the NCAA Tournament and four twenty-win seasons. In 1975, Henson moved to the University of Illinois to replace Gene Bartow, after Bartow left Illinois to replace John Wooden at UCLA. In 21 years at Illinois, Henson garnered 423 wins and 224 losses, and with a record of 214 wins and 164 losses in Big Ten Conference games. The 214 wins in Big Ten games were the third highest total ever at the time of his retirement. His best Fighting Illini team was the 1988-89 unit, which won a then-school record 31 games and went to the Final Four. At Illinois, Henson coached many future NBA players, including Eddie Johnson, Derek Harper, Ken Norman, Nick Anderson, Kendall Gill, Kenny Battle, Marcus Liberty, Steve Bardo, and Kiwane Garris, and was known for his trademark Lou-Do. Henson retired from Illinois at the end of the 1996-1997 season. In 1997, Henson returned to New Mexico State as interim head coach after Neil McCarthy was abruptly fired before the start of the season. Henson wanted to donate his time, but was told that state law didn't allow him to coach for free. He finally accepted a nominal salary of $1 per month. After a successful season, he was given his old job back on a permanent basis. His 1998–99 team won the Big West regular season and tournament titles—notably, the first time in Henson's career that he had won a conference tournament. He retired for good midway through the 2004–05 season due to non-Hodgkin's lymphoma. His second stint allowed him to regain his standing as New Mexico State's all-time winningest coach, passing McCarthy.
Health problems
In July 2007, Henson announced that he was again undergoing chemotherapy for the same strain of lymphoma that he had battled four years previously. He was undergoing treatment in Champaign, Illinois, where he lived in the summer. In July 2015, Henson once again entered chemotherapy for "bone marrow problems." Henson "returned to coaching" at age 82 as coach of the New Mexico House of Representatives team in a charity contest versus the New Mexico State Senate team on February 7, 2014. Henson died on July 25, 2020 at the age of 88.
Head coaching record
‡ New Mexico State ineligible for conference championship
* Record vacated due to NCAA infractions
† Henson resigned on January 22, 2005 and was replaced that day by interim head coach Tony Stubblefield; their collective record in the 2004–05 season was 6–24 for a sixth-place finish in the Sun Belt West division.
