Sint Maarten, country within the Kingdom of the Netherlands in the Lesser Antilles, northeastern Caribbean Sea. It occupies the southern third of the island of Saint Martin. The northern two-thirds of the island constitutes the French overseas collectivity of Saint-Martin.

St. Maarten (specifically the southern half of the island) belongs to the Kingdom of the Netherlands, but its political status is that of a "constituent country" rather than a mere colony or province. This means Sint Maarten is an autonomous country with its own government, prime minister, and parliament, while still sharing the Dutch Monarch and certain responsibilities—like defense and foreign policy—with the Netherlands. The northern half of the same island, known as Saint-Martin, is an "Overseas Collectivity" of France. This unique arrangement makes the island the smallest landmass in the world shared by two sovereign nations. Sint Maarten officially achieved its current status on October 10, 2010, following the dissolution of the Netherlands Antilles. While the citizens hold Dutch passports and the official languages are Dutch and English, the island operates with a high degree of independence in its day-to-day administration and economic policy, largely centered on its massive tourism industry. It is part of the "Dutch Caribbean" but is not a member of the European Union, though it holds "Overseas Country and Territory" (OCT) status.