If Scotland says Aye, what happens next?

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Picture this: It's September 19th and Scotland's voters, after three centuries as part of the United Kingdom, have said Yes to independence. First things first – there'll be an almighty party by the Yes campaign celebrating what many analysts have hailed as a positive, emotionally responsive, social media-savvy operation. But when Scottish National Party (SNP) leader Alex Salmond and his cohorts wake up the next day, they have at least 18 months' hard work ahead to get the new nation ship-shape for independence.

There would also likely be an outbreak of forced civility. The No campaign, and the rest of the U.K., would ultimately have to swallow their dire predictions and work with the other side to ensure a Scotland with the best chance of future economic success.

CNBC looks at some of the most probable moves in the early days of Scottish independence.


Sterling

Hold a lot of assets in sterling? Prepare to watch the trading screen through your fingers. The currency could fall to as little as $1.40 later this year – compared to $1.71 in July – according to Nick Beecroft, senior market analyst at Saxo Bank.

New Scottish currency

The only modern-day model we have for a country decoupling from sterling comes from Ireland. In this case, Ireland used sterling for seven years after independence in 1921, had a one-to-one relationship with the pound for a further five decades, and used the Bank of England as its central bank for a couple of decades.

After the bitter face-off between Yes and No camps over sterling during the campaign, Scotland's links with sterling will probably be quickly severed. A newly independent Scotland could use the euro while remaining outside the euro zone, like Montenegro. It could keep sterling, but then be forced to keep the Bank of England's influence over interest rates.


Scottish banks

After trumpeting their intention to move their corporate headquarters down South, financial institutions like Royal Bank of Scotland and Lloyds will have to put those contingency plans in place. Whether this means they will move jobs to the more expensive South at the same time has yet to be seen.

Banks would have to shore up their balance sheets – which could mean cutting down on lending. There are also worries about what will happen to sterling-denominated assets in the event of a new Scottish currency.


Oil

One of the most difficult issues following independence will be just how much of Scotland's dwindling North Sea oil assets it can claim – and how much the rest of the U.K. relies on revenues from these assets. Last year, North Sea oil generated £4.7 billion ($7.6 billion) in tax revenues for the U.K.

The Yes campaign is hoping to get 90 percent of the assets, but the Westminster government may be able to argue for a greater slice of the pie, as the negotiations over Scotland's independent future.

Rest of the U.K.

The U.K. would initially maintain its place as the sixth-biggest economy in the world.

If North Sea oil revenues are removed from the rest of the U.K., at the same time as a devaluation of sterling, the country's current account deficit could become "simply untenable" according to Albert Edwards, the notoriously pessimistic strategist at Societe Generale.

Trade

Scotland exports over 70 percent of its gross domestic product, much of it to the rest of the U.K. Once it becomes independent, it will have to begin negotiating new relationships with key markets like the U.S. and China.

European Union

For it to continue benefiting from the free flow of trade, money and labor that membership of the European Union provides, Scotland would have to apply as an independent state to be part of the trading bloc, and meet its standards for membership – a process that could take anything from 18 months (the optimistic forecast of the Yes campaign) to five years (U.K. lobby group Business for New Europe).


Election?

There is a U.K. general election scheduled for 2015, but given that Scottish MPs would not form part of a future Parliament, it may be delayed until after independence.

There are concerns that a Yes vote might lead to increased support for fringe parties within the rest of the U.K., such as the anti-EU U.K. Independence Party.