Everton have completed the signing of Brazil international Allan from Napoli with the midfielder signing a three-year contract at Goodison Park.
Allan will be reunited with manager Carlo Ancelotti, who he played 61 games under at the Italian club last year.
"It is a real pleasure to sign for Everton. I am immensely happy to be here," Allan told Everton's website.
"I hope, like I have done in my entire career, I contribute with my performances together with my teammates and that I put in some great games, great performances and win important things.
"It is a club with a rich history in the Premier League, has real ambition and then there is Professor Ancelotti.
"He has done everything possible to bring me here.
"It is the size of the Club and the name of the coach which means you don’t think twice about coming to Everton.
"I believe with my desire I can put in really good performances to win the fans over and I hope to win things as well. There will be a tremendous amount of dedication from me, a lot of dedication – a lot.
"I received a lot of messages from Everton fans and that made me really happy and confident in the work I can do here."