It was a case of third time lucky for Reds boss Kenny Dalglish after he had seen bids of £12million and £15million rejected by Villa for the 26-year-old England international winger.
And, after securing his switch to Anfield, Downing could not hide his delight at joining a club with Liverpool's 'tradition' and 'brilliant fans', who he is determined to bring success to.
Downing, who is Liverpool's fourth summer signing following on from Sunderland's Jordan Henderson, Blackpool's Charlie Adam and Roma goalkeeper Alexander Doni, told Liverpool's website: "It would be nice to win something. I'm sure that's the same objective for everyone, not just me personally.
"My aim is to be in the team, to play well and give something back because the manager has pushed the boat out to get me here, so hopefully I can give him something back.
"Getting a few goals and a few assists for the lads up front, that's what I'm hoping for."