Parker's coaching career began right after graduation at his alma mater, the University of Findlay (Ohio). He was there as an assistant basketball and head track coach. He moved to Bowling Green where he was an assistant basketball coach for six season. In 1982, he as named head coach at Wayne State where be began an incredibly successful run.
From 1982-1988 his teams posted a record of 120-56 and Parker became the winningest coach in school history. Averaging 20 wins per season, his teams won three Great Lakes Intercollegiate Athletic Conference titles and made three NCAA Division II tournament appearances. He was named GLIAC Coach of the Year twice (1984 and 1987) and was inducted into Wayne State's Athletic Hall of Fame in 2001.
He moved to the University of Southern California in 1989 where he was an assistant under head coach George Raveling. Parker assumed the role of interim coach on November 14, 1994 and remained in that position the next year, 1995-1996.
Leaving USC, Parker began his ten-year association with the Dallas Mavericks as an assistant under three different coaches. He joined the New Orleans Hornets staff in the 2007-2008 season where he stayed for three years.
Parker headed overseas in 2010 and spent one season coaching in China and two in Bahrain before returning to the Mavericks extended family in 2013 as an assistant with the Texas Legends of the NBA D-League.