O'Neill, 50, hired last May as the top assistant to Olson, currently is at the reins of the program as coach during Olson's leave.
"Kevin is our coach for now, and will be our coach in the future when Lute decides to retire," Livengood said. "It goes without saying, but let me say it again: the University of Arizona's appreciation for what Lute Olson has meant to our program is boundless."
"It's an unbelievable honor to follow Lute Olson," O'Neill said. "I'm thrilled to get the opportunity and will work to continue the superb tradition of Arizona basketball when Lute is done."
Olson has a career record of 780-280 (.736) in 34 seasons as an NCAA Division I head coach and 589-187 (.759) in 24 years at Arizona. Inducted into the Naismith Memorial Basketball Hall of Fame on Sept. 27, 2002, Olson is one of only 16 coaches in basketball history to tally 1,000 career victories (covering all levels; Olson also coached on the high school and junior college levels), and has the most Pac-10 wins (327) of any coach in league history.
During his 24-year tenure at Arizona, the Wildcats have won one national championship (1997), played in the national championship game (2001), participated in four Final Fours (1988, 1994, 1997, 2001), won 11 Pac-10 Conference titles, four Pac-10 Tournament crowns (1988, ‘89, ‘90, 2002) and been to the NCAA Tournament for 23 consecutive seasons, which is the longest active and second-longest streak in NCAA history (North Carolina, 27).
In his collegiate career, Olson has produced 52 NBA Draft picks, including 31 at Arizona, and coached 19 Wildcat All-Americans. He's led UA to 20 consecutive 20-win seasons and has 29 overall in his career, making him one of only three head coaches in NCAA history to record 29 or more 20-win seasons.
O'Neill has 11 seasons of experience as an NCAA Division I head coach, where he compiled a 152-165 (.479) record while at Marquette, Tennessee and Northwestern. O'Neill spent the last seven seasons in NBA circles, including the 2003-04 season as the head coach of the Toronto Raptors.
The Wildcats, ranked No. 19 by the Associated Press in this week's college basketball poll, are 7-2 heading into their game Wednesday at Neada-Las Vegas. The record counts on O'Neill's ledger as opposed to Olson's under NCAA coaching guidelines.