The long-awaited date of Scotland's independence referendum is set to be announced.
First Minister Alex Salmond will make a statement to MSPs at Holyrood. The Referendum Bill, laying out plans for the vote, is also expected.
Deputy First Minister Nicola Sturgeon said the announcement "marks a significant and important step in Scotland's independence journey".
The vote is taking place after the Scottish National Party won an unprecedented majority in Holyrood in the 2011 election.
While the media has speculated that the referendum would be held on October 18 next year, the Scottish Government has only said that it will take place in autumn 2014.
Mr Salmond's administration has already put forward legislation to allow 16 and 17-year-olds to take part in the crucial vote.
The question to be put to voters is almost certain to be: Should Scotland be an independent country? Yes/No.
The wording was changed after elections watchdog the Electoral Commission said use of the phrase "do you agree" in the original proposed question was biased towards a Yes vote.
Before the announcement Ms Sturgeon will visit engineering apprentices who will play an "integral part" in the events by welding the referendum date onto a piece of metal. She will be at Steel Engineering in Westway Park, Renfrewshire, a steel fabricator business which is developing the world's first community-owned tidal turbine and also making the world's largest wind turbine.
She said: "Today we will unveil the date for the 2014 referendum which marks a significant and important step in Scotland's independence journey... In an independent Scotland, it will be this Government's utmost priority to create a system that will encourage young people into work environments like these, allowing them to play a full, active role in our society."