Petr Cech has agreed to join Arsenal from Premier League champions Chelsea on a "long-term contract for an undisclosed fee", the Gunners announced on their website on Monday.
The 33-year-old Czech international goalkeeper made over 400 appearances during 11 years at Stamford Bridge after joining from French club Rennes, but has recently found himself playing understudy to Thibaut Courtois. (Also read: Arsenal need consistency, says Thierry Henry)
"I'm really excited about joining Arsenal Football Club and can't wait to join up for pre-season," said Cech.
"I have the same commitment to football, the same motivation and the same hunger for success as I had at the beginning of my career, and I love the challenges brought by the top quality players you face while playing in the Premier League.
"When Arsene Wenger spoke to me about his ambitions for this club, and how he saw me as part of this team, the decision was clear."
Arsenal manager Wenger added: "Petr Cech is a player that I have admired for a long time and I am very pleased that he has decided to join us.
"He has proven over many seasons that he is one of the outstanding 'keepers in the world and he will add great strength to our squad," the Frenchman said.
During his time with Chelsea, Cech's haul of 13 major trophies included four Premier League titles and four FA Cups, as well as the 2012 Champions League.
In the same period, Arsenal had to make do with three FA Cup triumphs, including a 4-0 victory over Aston Villa in last season's final.
Neither Wojciech Szczesny or David Ospina has been completely convincing between the posts for Arsenal, with many pundits believing Wenger needed to sign a top-class goalkeeper if the Gunners were to challenge for the Premier League title.
Prior to Cech's move across London, Chelsea captain John Terry said he would improve Arsenal, who finished third in the Premier League last season, by 12 to 15 points.
"If they (Arsenal) do get Pete, that will strengthen them for sure," centre-half Terry told talkSPORT radio. "He will save them 12 to 15 points a season."
Arsenal finished 12 points behind Chelsea last season.
Former Gunners goalkeeper Bob Wilson, also speaking before the transfer was confirmed, was in no doubt of Cech's quality.
"So, he's 33 now, he still has five or six seasons of greatness in him and he is going to give Arsenal that assurance at the back that they really need," Wilson, a member of the Gunners side that won the "Double" in the 1970/71 season, told BBC Radio Five.
"When a side wins the league it starts with the man at the back and usually when a side wins the league the goalkeeper usually has an amazing season.
"You know, people will look at the two who are there -- Wojciech Szczesny and David Ospina -- and the point really is that if you can improve your team in any way you'd be fools not to do it," Wilson added.