Scotland voted No to independence in 2014 following an often frenzied campaign and a record-breaking turnout of 84.6%.
But things have changed since then - most notably the decision by the UK to leave the European Union.
So have Scottish voters changed their minds?
Ruairidh Forbes was so keen to vote No to independence in 2014 that he delayed moving from Edinburgh to London where he was due to begin a PhD in physics.
Ruairidh, from North Berwick, says he was not convinced that the financial security of an independent Scotland could be guaranteed.
But now he plans to vote Yes.
"I am worried about a decline in science and technology funding in the UK after Brexit," Ruairidh explains.
"Independence is our best shot at staying in the EU."
Ruairidh is now three years into his doctoral studies and sees the benefits brought to the UK by the Â£7.6bn received from the EU for scientific research in 2007-13.
"The British government relies on EU funding to prop up UK science and technology - I am worried that the sector will collapse once Brexit happens.
"This means that we won't be able to take part in visionary research or cutting-edge projects like the Large Hadron Collider at Cern in Switzerland."
"There are no contingency plans being laid at Westminster."
Although there is no guarantee that an independent Scotland would become a member of the EU, Ruairidh believes signs suggest that voting for independence is Scotland's best chance to preserve science and technology research.
But is he worried that this is also a vote for the SNP, a party that he does not support?
"I don't think they are the right party for Scotland - I'm not a nationalist, I see myself as British.
"But I believe the independence movement is motivated by social issues and this is a unique opportunity for fairer politics."
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"I used to think Scotland had the ability to do well alone," explains Nichola Dadds, who is 50 and lives in Edinburgh.
"I voted Yes to independence in 2014 but a lot has changed since then."
Nichola wanted to stay in the EU - but now that Britain has decided to leave, she is worried that as a small country Scotland would be marginalised in the European Union.
"Much of Scotland's trade is with the UK or non-EU countries like China or the US - if we left the UK, I am not convinced we could get a good trade deal.
"I would be concerned about joining the EU as a small country. Look at countries like Ireland and Italy - they have little say in Europe," explains Nichola.
"I believe if Scotland became independent from the rest of the UK we would end up beholden to the EU and my thoughts are, 'Better the devil you know,'" Nichola says.
Instability caused by the fallout from Brexit is another reason why she changed her mind.
"I want to vote for stability and security. We have had enough of referendums - it is time to get used to what is going on instead of causing more disruption."
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Keeping Scotland out of the European Union is Steven Calvert's motivation to change his vote from Yes to No.
In 2014 Steven, who lives in Inverness, voted for independence as a protest vote against the Conservative government in Westminster.
"I voted yes to escape David Cameron and rule by a party that Scotland did not vote for.
"But now I plan to vote No - I want Scotland to be out of the EU and independence could jeopardise that."
Steven wants to set up a seafood export business and opposes the fishing regulations that come with EU membership: "People here talk about how the EU has made it hard for small fishermen to make a living.
"Big trawlers come in from countries like Spain, and we can't find a place to fish.
"I think Scotland leaving the EU gives us the chance for a more sustainable quota, hopefully encouraging restoration of the Scottish fishing industry. That would offer good jobs to young people, especially in rural areas."
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Jessica Orr felt ashamed in 2014 that she did not vote for independence.
"I'm very sensible and pragmatic - I felt that it was too risky, but all my friends and colleagues voted Yes," she explains.
Now she has a second chance, she plans to do things differently.
"I feel like after Brexit and President Trump's victory, politics has become really degraded and I've realised how positive the independence idea is.
"I'm frustrated that we've been forced to leave the EU despite the fact that Scotland did not vote for it.
"Without the EU, I feel like we will be worse off, and I am frustrated about the changes to immigration policies in the UK.
"Scots are not represented at Westminster and I feel like Scottish political leaders have more integrity than those in Westminster or the US."
By Georgina Rannard, UGC & social news
First Minister Nicola Sturgeon has announced that she is seeking a second referendum on Scottish independence to take place before Britain leaves the European Union.