Juventus entered the season led by Igor Tudor after making his interim spell permanent in the summer.
However, he wouldn't last long in the role, with the club from Turin relieving him of his duties following an eight-match winless run that left them eighth in Serie A and 25th in the Champions League, outside the playoff spots.
Spalletti was quickly reported to be the most likely replacement, with the Italian media stating that he'd sign a short-term deal that would be extended if he secured Champions League qualification, and such an appointment has now been confirmed.
"We are delighted to welcome a coach with such expertise and experience to the Bianconeri family," a club statement reads. "Welcome to Juventus and good luck, coach!
Spalletti was most recently in charge of the Italian national team, where he was sacked after under two years following a 3-0 loss to Norway that damaged the Azzurri's hopes of automatic qualification for the World Cup. Prior to that, he'd failed to take them past Switzerland in the round of 16 at EURO 2024.
He enjoyed far more success in the job before that though, leading Napoli to their first Serie A title since 1990 in the 2022/23 season, becoming a club legend in the process.
Such is his connection with the club from Naples that his appointment is seen by some as somewhat controversial. After winning the league with them, he got their badge tattooed on his arm and stated he'd never manage another Italian club.
However, while the 66-year-old's time at Napoli as well as his tenures at Roma and Inter may upset some, that experience is undoubtedly appealing to Juve given their lack of success under less seasoned coaches in Tudor and Thiago Motta.
His time with the Old Lady will begin with a trip to Cremonese on Saturday night.