As part of a Government move to ensure that the highest court in the country is completely independent from those who make the law it created the Supreme Court, which will occupy its own new building and be made up of 12 judges.
Until now the most senior court was made up of the Appellate Committee of the House of Lords and the Judicial Committee of the Privy Council. The House of Lords and the Privy Council are parts of Government, but The Supreme Court will not be connected to Government at all.
The Court said that it would now be "explicitly separate from both Government and Parliament".
Eleven of the 12 judges that form the Appellate Committee of the House of Lords will become judges at the Supreme Court. One, Lord Neuberger, is moving to the Court of Appeal, where he will be head of its civil division.
Lord Neuberger has expressed reservations about the new structure and has said that the very independence from Government that is its founding principle might lead it to assume too much power.
"The danger is that you muck around with a constitution like the British constitution at your peril because you do not know what the consequences of any change will be," he told BBC Radio 4 earlier this month. "[There is a risk of] judges arrogating to themselves greater power than they have at the moment."
Like the House of Lords, the Supreme Court will hear appeals from the Court of Appeal in England and Wales and the Court of Session in Scotland. It will be up to the Court of Appeal and the Supreme Court to decide which cases it hears.
There will be no appeal available from the Supreme Court, though if there is a question of interpretation of European Union law then the Court must ask the opinion of the European Court of Justice (ECJ).
The Court will be housed opposite the Houses of Parliament in London in a building that used to be a criminal court.
The duties of the court will differ according to where cases began. "The Court will hear appeals on arguable points of law of the greatest public importance, for the whole of the United Kingdom in civil cases, and for England, Wales and Northern Ireland in criminal cases," according to the Court.
"The Supreme Court also decides devolution issues, that is issues about whether the devolved executive and legislative authorities in Scotland, Wales and Northern Ireland have acted or propose to act within their powers or have failed to comply with any other duty imposed on them," it said.