Ings has joined the club on an initial season-long loan, after which the deal can become permanent in July 2019 for £18million.
Ings arrived at Liverpool in 2015 after a great season with Burnley and was expected to do big things with the Reds but two serious knee injuries put paid to that and he is now on a mission to resurrect what was a hugely promising career.
By the time he recovered he was unable to break into the dynamic front three, but Liverpool were eager to get maximum value for a player who had broken into the England squad prior to his injury setbacks.
It may seem odd that the man set to benefit most from pre-season is a player who is yet to kick a ball for Southampton but that is the case for Danny Ings, after it became clear the Saints desperately need an attacking boost.
"There was significant competition for Danny, with a lot of clubs keen to complete a deal for him, so we're clearly delighted that he chose to join us", said Southampton manager Mark Hughes.
"But we won't just miss his character because he is a footballer who has all the tools".
It was unclear whether Southampton had got the paperwork in on time.
"We all know his story and the bad luck he has had since then".
"It's why the other emotion is that of being pleased for Danny that he has such a good move and his future is now very bright".
"It's his home, his family is there, it's his boyhood club".
"I think fans respond to that as well".
Liverpool will receive £18 million up front, with a further £2 million in add-ons, and negotiated a 20 percent sell-on clause in their deal.
The former Hamble Community College and Brockenhurst College student is ready for action, according to Hughes, meaning he could be in action in the Premier League curtain raiser against Burnley at St Mary's on Sunday.
Manager Jurgen Klopp did not want the striker to leave Liverpool, but was understanding of his desire for game-time and willing to sanction a move.