Now the Trans Pacific Partnership talks have concluded, New Zealand and the 11 other countries must tick several boxes before the agreement can be brought into force.
Under a rule set by the United States, any agreement cannot be signed until 90 days after negotiations end, to allow time for full consideration of its pros and cons.
The same rule also says the agreement's full text must be made available to the public after 30 days.
In New Zealand, the Ministry of Foreign Affairs will provide a report to the Cabinet on the costs and benefits.
The Cabinet will then decide whether to approve the agreement.
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Once the Cabinet approves the deal, the full text will be tabled in Parliament.
It will then be scrutinised by a parliamentary committee, which will hear submissions from the public.
New Zealand will likely have to change its laws to bring them into line with the agreement. This would probably be done through a single piece of legislation, and was likely to include changes to copyright, tariff and patent laws.
The bill would provide a chance for a parliamentary debate on the agreement, but only on the parts of the law which need to be changed.
This process could not alter the text of the agreement.
After the bill passes and any other policies or regulations have been brought into line with the agreement, the Government will ratify the deal.
Once other countries have followed a similar process, the agreement will come into force.
There is no set timeframe for this to happen, though Japan has proposed a minimum two-year limit.
The evolution of the TPP:
• 2001 NZ-Singapore - begun by Lockwood Smith, it was concluded in 2001 under Helen Clark's Labour Government.
• 2002 Pacific Three Closer Economic Partnership (P3CEP) NZ-Singapore-Chile
• 2005 P4 - NZ-Singapore-Chile-Brunei or Trans Pacific Economic Partnership agreed but without investment and financial service chapter.
• 2008 P4 was about to conclude investment chapter under Phil Goff when US (Bush administration), Australia, Vietnam and Peru asked to join.
• 2009 Obama administration adopts TPP as goal.
• 2010 Malaysia joins and TPP negotiations begin.
• 2012 Canada and Mexico join negotiations.
• 2013 Japan joins negotiations.