Jim Mitchell Cleamons was born on September 13, 1949 in Lincolnton, North Carolina. He went to Ohio State University.

He was drafted by the Los Angeles Lakers as the 13th pick in the 1971 draft. Cleamons was a member of the 1972 championship team that won 33 staright games and posted a 69-13 record. (best at time and second best all time). In 1976 Cleamons was selected onto the NBA All-Defensive 2nd team.

Cleamons has served as assitant coach under Phil Jackson in both Chocago and Los Angeles. He was the head coach for just over a year for the Dallas Mavericks in 1996-1997. He was an assitant coach for the New Orleans Hornets durin the 2004-2005 season before coming back to work under Jackson.