After leading the Coffeyville Junior College basketball team to the NJCAA National Championship with a 32–0 season in 1962, he took his high-octane offense to Southern Illinois University, replacing Harry Gallatin, who left to take the head coaching job with the St. Louis Hawks.

In 1967, missing out on the NCAA Division II tournament after two successive second-place finishes, Hartman's Salukis won the NIT Championship, which was much more highly regarded then than it is today.

Hartman is credited with introducing a different two-tone uniform, including lavender tops and purple shorts, for Kansas State to wear during its away games, which the Wildcats used from 1973 to 1982.

[2] In 1983, he led the United States men's national team, which included Michael Jordan and Chris Mullin, to gold medal at the 1983 Pan American Games in Caracas, Venezuela.

His daughter, Jackie, lives in Manhattan and served as the chief of staff for the president of Kansas State University.