Inler seals Napoli switch
"I've chosen Napoli to win," the defensive midfielder, famous for his tenacity, told the club's website after joining from Udinese.
"I'm happy, I'd decided to come to Napoli a while ago. This is a great club, a beautiful family and a special public," he said.
"When I played at the San Paolo with Udinese, I realised that the warmth of this crowd is extraordinary."
Inler, at FC Basel and FC Zurich earlier in his career, played for Udinese for four seasons, during which he also became a regular for Switzerland.
The 27-year-old took over the captaincy of the Swiss side last season after the international retirement of record scorer Alexander Frei.
Napoli will play in the Champions League next season after their third-place finish in Serie A.