Jeremy Corbyn has been re-elected as Labour leader, comfortably defeating his challenger Owen Smith.
He won 61.8% of the vote, a larger margin of victory than last year.
He vowed to bring Labour back together, saying "we have much more in common than divides us", insisting the party could win the next election as the "engine of progress" in the country.
More than half a million party members, trade unionists and registered supporters voted in the contest.
In a result announced on the eve of Labour's party conference in Liverpool, Mr Corbyn won 313,209 votes, compared with Mr Smith's 193,229.
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The BBC's assistant political editor Norman Smith said it was a big win for Mr Corbyn which boosted his mandate. The result raised "serious questions" for Mr Corbyn's critics, he added.
One critic of Mr Corbyn said the leadership question was now "settled" but others said the Labour leader needed to heed calls for change.
Mr Corbyn said he was "honoured" to have been elected in a contest that followed months of tension with many Labour MPs and urged people to "respect the democratic choice that has been made".
Addressing supporters, Mr Corbyn said he and his opponents were part of the "same Labour family" and everyone needed to focus their energy "on exposing and defeating the Tories".
"We have much more in common than divides us," he said. "Let us wipe that slate clean from today and get on with the work that we have to do as a party," he said.
Recognising that the election had been "partisan", he condemned online abuse of Labour MPs and supporters which he said "demeaned and corroded" the party.
Mr Corbyn was first elected Labour leader in September 2015, when he beat three other candidates and got 59.5% of the vote.
Turnout was higher this time around, with 77.6% of the 654,006 eligible party members, trade union members and registered supporters - 506,438 in total - confirmed as taking part.
Mr Corbyn won comfortably in each of the three categories - winning the support of 59% of party members, 70% of registered supporters and 60% of affiliated supporters.
'Leadership settled'
Despite winning the leadership in a vote of the wider membership and registered supporters last year Mr Corbyn, who spent three decades as part of a marginalised leftwing group of Labour MPs in Parliament, has never had the support of more than about 20% of Labour's MPs.
And the contest came about after more than 170 MPs supported a motion of no confidence in their leader - the vote came after dozens quit his shadow cabinet and other frontbench roles.
There has been speculation that a number of criticial Labour MPs, including some who resigned from Mr Corbyn's shadow cabinet in June over his leadership in the wake of the EU referendum, could return in an attempt to heal the divisions over the party's future direction.
Labour MP Chuku Umunna said the "leadership issue was settled" and Mr Corbyn, through his re-election, was the party's "candidate to be prime minister".
Shadow cabinet minister Jon Ashworth said MPs needed to respect the "handsome margin" of victory but that the leader needed to consider calls for shadow cabinet elections to be reinstated.
Mr Smith - a former work and pension spokesman - has said he will not serve under Mr Corbyn and will remain on the backbenches.
And Labour MP Louise Ellman said Mr Corbyn must appeal to more than his "cheering fans" and the public at large weren't "impressed with him and that needs to change".
"It no good being surrounded by people who already agree with you. That is not enough."