Scotland, England's junior partner in the United Kingdom since 1707, will decide Thursday whether to become independent once again. The referendum and the issues.

Q: What will voters consider exactly?

A: The question on the ballot is: "Should Scotland be an independent country?"

Q: How did a seemingly fruitful union reach the breaking point?

A: Prime Minister David Cameron insisted on a vote in a deal in 2012, excluding a third option of giving the Scots more autonomy — which he is now offering anyway.

Q: Who's who?

A: The pro-independence campaign is led by Alex Salmond, whose Scottish National Party won an unexpected majority in the Scottish Parliament in 2011.

The anti-independence camp, which calls itself Better Together, is a coalition of British political parties.

Q: What's at stake?

A: Hard economics have dominated the debate: What currency will Scotland use? How will revenue from North Sea oil reserves be divided (or will it)? Who will shoulder the burden of public debt?

If Scotland votes to separate, it will take 18 months of negotiations before independence is declared. Scotland already administers many of its own affairs. Some economists say an independent Scotland would be too poor to maintain its welfare state.

Britain also has a lot on the line: If Scotland and its more pro-European voters leave, Britain might leave the European Union.

Q: Who can vote?

A: The referendum is open to voters as young as 16, even though the national voting age is 18. Only residents of Scotland can vote.

Q: Which side is winning?

A: Until recently, the anti-independence campaign maintained a comfortable lead in opinion polls. But as the vote approached, the two sides were neck and neck.

Q: Will the queen have to go?

A: Salmond has promised fellow Scots that they get to keep Elizabeth as their head of state, Canadian-style — although future Scottish voters could always change that.

Q: What would Britain look like without Scotland?

A: If Scots vote to secede, Britain will be less great: It will lose 5.3 million residents, more than 8 percent of its population.

Q: Will the Union Jack — which combines the colors of England, Scotland and Ireland — come down?

A: The College of Arms, the official register for coats of arms, has said that the flag would not technically have to be changed if the queen remained the head of state of an independent Scotland.

New York Times