The former Blackpool captain, who has completed his medical, becomes the club's second big addition of the summer following Jordan Henderson's ?16m switch from Sunderland.
'I am absolutely delighted to be here,' he said. 'It has been a long process but now I can't wait to get startedand hopefully this will be a successful period in my career and in the club's history.
You'll never walk alone: Liverpool boss Kenny Dalglish shows Charlie Adam into the club's Melwood training ground
'I see this as the perfect development for me to come here, play with such wonderful players and hopefully help the team to win trophies, because that's the most important thing.
'I'm delighted to be able to walk out on the same pitch as some of the players here. There are good players at the club, top, top players who I want to learn from. I want to become a better player and hopefully bring something to the team.
'Hopefully we can have a successful period because it's been missing now for a couple of years. At the end of the day you get judged on trophies and as a footballer you want to win as many as you can. This club has had a lot of success over the years, so let's get back to doing that.'
'Liverpool is a massive club with terrific players and a terrific manager. You have seen since the new manager came in the forward strides that have been made. Kenny has a terrific respect from players and people in the game. He is a wonderful manager and it's an honour to be able to say I'm going to be able to play for Liverpool.
Enlarge In the driving seat: Dalglish has his man as the Liverpool boss drives Adam to the club's training ground
'I tasted Anfield last year, scoring here (in the Seasiders' 2-1 win) was an unbelievable feeling and hopefully I've got many more days like that as a Liverpool player.'
Rangers boss Ally McCoist will get to spend an ?850,000 windfall from Charlie Adam's move to Liverpool.
The Ibrox club are due a slice of the?9m fee from Anfield through a sell-on clause agreed when Adam left Glasgow for Blackpool in a ?500,000 deal two years ago.
Blackpool boss Ian Holloway will alsotake ?250,00 from Adam's move. A clause in Holloway's contract entitles him to 2.5 per cent of the fee the Tangerines will receive.
Curler: Adam impressed with his set-pieces in the Premier League last season
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