Chelsea have appointed Maurizio Sarri as their new head coach on a three-year contract.
The 59-year-old Italian takes over at Stamford Bridge from Antonio Conte, who was sacked on Friday.
His first game in charge will be in the friendly with Perth Glory at Optus Stadium in Perth on July 23.
During three years with Napoli, Sarri helped the club to two second-placed finishes in Serie A and won the Coach of the Year award in 2017.
Sarri said: "I am very happy to be coming to Chelsea and the Premier League. It is an exciting new period in my career."
"I look forward to starting work and meeting the players on Monday ahead of travelling to Australia, where I will be able to get to know the squad and begin our match action.
"I hope we can provide some entertaining football for our fans, and that we will be competing for trophies at the end of the season, which is what this club deserves."
Chelsea director Marina Granovskaia said: "We are delighted to welcome Maurizio and are looking forward to him bringing his football philosophy to Chelsea.
"Maurizio's Napoli side played some of the most exciting football in Europe, impressing with their attacking approach and dynamism, and his coaching methods significantly improved the players at his disposal.
"He has plenty of experience in Serie A and the Champions League and we know he is relishing the chance to work in the Premier League."
Conte's future was finally resolved after months of speculation and despite the Italian overseeing pre-season training earlier this week.
The 48-year-old had a year remaining on his contract, but has left the Blues 55 days after lifting the FA Cup in his final match in charge.
Conte led Chelsea to the 2016-17 Premier League title in his first season as boss, reviving the side from a 10th-placed finish the previous campaign.
Finishing fifth in the league in 2017-18, missing out on Champions League qualification, and friction with the Chelsea hierarchy and influential players prompted Conte's departure after two seasons.
Sarri becomes Chelsea's 13th permanent boss of Roman Abramovich's ownership, which began in June 2003.