Angelo Alessio was named as a the surprise choice to succeed Steve Clarke as Kilmarnock manager on Sunday.
The 54-year-old Italian made his name as number two to Antonio Conte at Chelsea, Juventus and with the Italy national team.
Conte, who left Chelsea last year, recently returned to frontline management in Inter Milan boss but Alessio decided not to follow him as he looked to land a top job himself.
Alessio told Killie's official website: "It is a real honour for me to be named Kilmarnock manager.
"I've spent a lot of time researching and gathering information about the club and everyone I spoke to had nothing but positive things to say about Kilmarnock.
"I can't wait to get to work with the players and staff on the training pitch and building on the strong foundations left by Steve Clarke."
Clarke's assistant Alex Dyer had been among the front-runners for the job before Alessio's name emerged over the weekend.
Darren Moore, Simon Grayson and David Moyes had also been linked with the post at Rugby Park.
Alessio represented Juventus, Bologna and Bari during his playing career in the 1980s and 1990s before he moved into coaching as an assistant at Napoli.
He first joined forces with Conte at Siena in 2010 before they went on to win three Serie A titles together at Juve and the Premier League at Stamford Bridge. They also oversaw Italy's Euro 2016 campaign, at which the side reached the quarter-finals.
Alessio takes over from Clarke, who left last month to take over as Scotland manager after guiding Killie to third in the Ladbrokes Premiership.
Club director Billy Bowie added: "On behalf of the board of directors, I'm delighted to name Angelo as the new manager of Kilmarnock FC.
"We were extremely impressed by the calibre of the candidates for the vacancy but Angelo's knowledge and passion for the role really shone through.
"This is a hugely exciting period for Kilmarnock as we celebrate the club's 150th anniversary and play European football for the first time in 18 years and
we're looking forward to this new chapter with Angelo at the helm."