By SABC Sport
19th June 2023
O'Neil guided the Cherries to Premier League safety last season following the dismissal of Scott Parker at the end of August.
Andoni arrives at the Vitality Stadium following the expiry of his contract at Rayo Vallecano, where a three-year spell ended with an 11th-placed finish in La Liga last season.
He had previously taken Segunda División side Mirandés to the same stage of the domestic cup in 2019/20, for only the second time in the club's history.
He started his managerial career in Cyprus with AEK Larnaca where he led his side in the group stage of the Europa League.
Bournemouth owner and chairman Bill Foley said. "We're so excited to welcome Andoni to the club. With his contract in Spain coming to an end this summer we wanted to act quickly.
"He was highly sought after by other clubs across the continent, and his style of play has been an important factor in making this decision.
"His achievements in Spain have certainly been very impressive, and we're confident that he is the right man to lead our next chapter.
"We have identified a number of targets in the transfer market, which along with our January additions will supplement our strong playing squad to give Andoni the best chance to consolidate our Premier League status and keep progressing."
O'Neil initially took over from Parker on an interim basis following a 9-0 thrashing at Liverpool before being appointed permanently in November.
The 40-year-old took 36 points from his 34 top-flight games in charge to help the Cherries avoid relegation following promotion from the Championship.
Foley added: "Gary's achievement last season is one I will always be grateful for. This has been a difficult decision, but it has been made with great consideration to best position ourselves ahead of the coming season.
"We have also identified a number of significant targets in the transfer market this summer and believe this change in direction will provide us with the best platform from which to build.
"Gary will go on to have a long career as a head coach or manager, but we feel that, at this moment in time, a change is in the best interests of this football club."