Having tried to land the Blackpool star in January, Liverpool finally agreed a fee in the region of ?9million for the Scotland midfielder.
Adam, who has completed his medical, becomes the club's second big addition of the summer following Jordan Henderson's ?16m switch from Sunderland.
You'll never walk alone: Liverpool boss Kenny Dalglish shows Charlie Adam into the club's Melwood training ground
Where Dalglish fits Adam and Henderson into his new-look team will be pondered by fans but there is little doubt the manager's recruitment drive is geared, in many ways, to ensuring Carroll gets enough ammunition to live up to the billing of a ?35m striker.
One of Adam's qualities is his pinpoint set pieces, while Liverpool's relentless pursuit of Stewart Downing a player well known for the accuracy of his crosses offers further proof that they are determined to give Carroll maximum assistance from the flanks.
Liverpool have had a ?15m offer for Downing rebuffed but are unlikely to be deterred by Aston Villa's hardline stance and will return with an improved bid for the England winger, who has his heart set on a move to Anfield.
Enlarge In the driving seat: Dalglish has his man as the Liverpool boss drives Adam to the club's training ground
Villa are adamant their England star is not for sale and are even prepared to invite him to restart talks on a new contract, although he has two years remaining on his current deal. Villa feel they are under no pressure to sell having allowed Ashley Young to join Manchester United this summer.
Downing, last season's player of the year, must decide whether he is prepared to take a financial hit by asking to leave, not to mention risking the wrath of fans if a move fails to materialise.
Curler: Adam impressed with his set-pieces in the Premier League last season
Liverpool had missed out on a number of targets, leaving some to wonder whether a summer of frustration loomed, but things have picked up in the last 48 hours.
The quest to bring in cover for goalkeeper Pepe Reina is almost over, with Roma's Brazil international Doni expected to travel to Merseyside for a medical within the next 36 hours. England full back Glen Johnson also signed a contract extension until 2015 on Wednesday.
New arrival: Doni looks set to join Liverpool as cover for Pepe Reina
Director of football Damien Comolli said: 'We are delighted. We were in talks for a few weeks but it was easy to find an agreement because he wanted to stay and we wanted him to stay.
'We are very pleased he wants to commit long term and I think he was pleased we went to him and asked him to commit long term.'
The Reds have also been boosted by Glen Johnson committing his long-term future to the club after signing a contract extension.
The England defender has been rejuvenated after Dalglish's arrival in January, playing well out of position at left-back.
Johnson said: 'I'm very pleased. I've been here a couple of years and it's great to be staying here for a few years longer now.
Staying put: Glen Johnson has committed his long-term future to Liverpool
'For the club to want me to be here is a great feeling and I did not have to think twice about signing.
'I think I am improving all the time at Liverpool. You're never too good to improve - and my aim is to just keep improving.
'With the squad we've got now, the backroom staff and the way things are going, things are looking positive. The club is looking to bring a few more players in, so the future is looking bright.
'We've made a couple of good signings already and with a few more we will be a right force in the coming season.
'I'm quietly confident (about the new season). If we take it game-by-game I think we'll do well.'
Adam closes in on Anfield move as Liverpool agree ?8m fee for Blackpool aceLiverpool ramp up bid to sign Downing but Aston Villa reject ?15m offer We won't waste ?35m Carroll cash, insist Toon as Llambias defends spendingAll the latest Liverpool news, features and opinion