Sint Maarten is an "island territory" (eilandgebied in Dutch), a component of the Netherlands Antilles comparable to a municipality.  The Netherlands Antilles are part of the Kingdom of the Netherlands though not in the European Union.  A planned restructuring of the Netherlands Antilles will see Sint Maarten become a separate country within the Kingdom of the Netherlands (like Aruba and the Netherlands Antilles are now).  This dissolution was scheduled to enter into force on December 15, 2008, but was temporarily postponed.

The governments of The Netherlands, the Netherlands Antilles, and the island governments of Curaçao and St. Maarten reached an agreement regarding a new date for country status in early October 2009.  As of October 10, 2010, the Netherlands Antilles will cease to exist.  The countries of Curaçao and St. Maarten will be formed in its place, whereas the remaining islands will become public entities of The Netherlands.  

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"The Daiy Herald: Constitution Unanimously Adopted"