David Cameron has promised a "new and fair" constitutional settlement for the entire United Kingdom after Scotland voted to reject independence and remain part of the United Kingdom.
The British Prime Minister hailed the referendum vote - 55% to 45% against breaking away from the UK - saying it represented the "settled will" of the Scottish people which should put an end to the independence debate "for a generation".
Following a campaign which galvanised all of Scotland, he vowed that promises made by the three main Westminster parties to devolve more powers to Holyrood would be "honoured in full", with draft legislation in January.
But speaking on the steps of Downing Street, he made clear that they would go hand in hand with a "balanced" new constitutional settlement covering England, Wales and Northern Ireland.
In particular, he said there would have to be reform at Westminster to address the thorny issue of "English votes for English laws", suggesting that Scottish MPs would no longer be able to vote on exclusively English issues.
The plan was dismissed by Labour - whose chances of forming a majority government at Westminster are likely to depend on Scottish votes - as a "knee-jerk reaction" driven "more by politics than by a considered judgment of the needs of the constitution".
However Conservative MPs made clear they were not prepared to tolerate a situation where Scottish MPs could vote on the level of income tax for England while income tax in Scotland was decided in Holyrood.
At the end of a dramatic night, Scottish First Minister Alex Salmond finally conceded shortly after 6am that his long-cherished dream of leading his country to independence was over.
"Scotland has by a majority decided not at this stage to become an independent country," he said in a speech to supporters in Edinburgh.
"I accept that verdict of the people and I call on all of Scotland to follow suit in accepting the democratic verdict of the people of Scotland."
A jubilant Alistair Darling, who led the Better Together campaign, said it was a "momentous result" for Scotland and for the United Kingdom as a whole.
"The people of Scotland have spoken. We have chosen unity over division and positive change rather than needless separation," he said.
"By confirming our place within the Union, we have reaffirmed all that we have in common and the bonds that tie us together. Let them never be broken."
With the votes from all 32 council areas in, the result was a victory for the No camp by 2,001,926 votes to 1,617,989 - on a record 84.5% turnout.
The result - which was more comfortable for the Better Together campaign than opinion polls had suggested it might be - was greeted with relief in No 10, where there were fears that a Yes vote could have triggered a major political and constitutional crisis.
"The people of Scotland have spoken and it is a clear result. They have kept our country of four nations together and like millions of other people I am delighted," Mr Cameron said.
"Now the debate has been settled for a generation, or as Alex Salmond has said: 'Perhaps for a lifetime'. So there can be no disputes, no re-runs, we have heard the will of the Scottish people."
The Prime Minister underlined his commitment to greater devolution of power to Scotland with an announcement that Glasgow's Commonwealth Games supremo, Lord Smith of Kelvin, would oversee the process.
However his promise of reform at Westminster to ensure that "the millions of voices of England" were also heard, opened up the prospect of a prolonged new political struggle leading all the way to the next general election and beyond.
"The question of English votes for English laws, the so-called West Lothian question, requires a decisive answer, so just as Scotland will vote separately in the Scottish Parliament on their issues on tax, spending and welfare, so too England as well as Wales and Northern Ireland should be able to vote on these issues," he said.
For Labour, shadow foreign secretary Douglas Alexander accused the Prime Minister of a "fairly knee-jerk reaction which ... may well have been driven more by politics than by a considered judgment of the needs of the constitution".
At the same time, Mr Cameron is under pressure from Conservative MPs who warned it was "inconceivable" that Scottish MPs would be able to continue voting on English affairs once tax-raising and other powers are passed to the Scottish Parliament.
Former cabinet minister John Redwood said: "What we first of all need to ensure is that all these matters are settled in England by English MPs without the help and advice of their Scottish colleagues.
"We as the English Parliament must settle the English income tax rate. It would be quite inconceivable that Scottish MPs would vote on the income tax rate for England - that may be higher than the Scottish one - that they weren't going to be paying."
The Leader of the Commons, William Hague, who will chair a Cabinet sub-committee to examine the issue, said that if the parties were unable to reach agreement, they would have to settle the matter at the general election.
"We have to discuss this with the other parties. If there is no consensus, then it is something which at the general election the parties will have to stake out their positions on," he said.