Would Scotland automatically be independent after the votes are counted?
The referendum on September 18 is a vote on whether Scotland chooses to be independent. But if the "yes" camp wins, the country isn't immediately independent. According to present plans, March 24, 2016 would be the key date. Various political and economic questions would have to be solved by then.
Would an independent Scotland still be a member of the European Union and NATO?
If Scotland were to secede from the UK, a new state would emerge in the spring of 2016, following a transitional phase. This new state would have to apply to join the EU. The same is true for NATO: Presumably, a new Scottish state would no longer be a part of the North Atlantic Treaty Organization after the transitional phase, but would have to apply for membership. All NATO member states must agree to accept a new applicant.
What does Scottish independence mean for Europe?
Many European states are worried about the referendum. In general, the Scots are viewed as more Europe-friendly than the rest of the UK, so Scotland's split from the UK would strengthen the EU skeptics' camp: If Britain holds a referendum on EU membership as planned in 2017, the four million missing votes from Scotland could be a crucial factor paving the way for a euroskeptic victory.
An independent Scotland could also impact independence movements in other countries. Spain and Belgium fear a rise of separatism, and in the United Kingdom, Scottish independence could foreshadow a similar move in the near future by Northern Ireland.
What would an independent Scotland's currency be?
The pound sterling would be Scotland's currency until March 2016. Past that date, London has categorically dismissed a currency union. Scotttish Prime Minister Alex Salmond announced plans to keep the pound as the primary currency all the same - if need be, without British permission. In that case, Scotland would not have a central bank and would not be in a position to print additional money.
Should Scotland join the EU, introducing the euro might well be a condition for membership. Accession candidates must first align their currency with the euro before formally adopting the single currency.
Creating a new currency is another option. Scotland already prints its own Scottish pound notes that are firmly aligned with the British pound. If need be, the government could devalue a currency of its own, and thus influence interest rates to plug potential holes in the budget.
What about the UK's national debt?
The government in London has already signaled it will assume responsibility for the complete national debt if Scotland votes for independence. After an interim phase, Scotland would then be expected to bear a "fair and proportionate share of the UK's current liabilities." Whether that share depends on economic performance or the share of the population is unclear - the former option would certainly be more favorable for Scotland.