St. Martin/Saint Martin is an island in the northeast Caribbean, approximately 300 km (186 miles) east of Puerto Rico. The 87 km² island is divided roughly 60/40 between France (53 km²) and the Netherlands (34 km²); however, the Netherlands side has the larger population. It is the smallest inhabited sea island divided between two nations, a division dating to 1648. The southern Dutch half comprises Sint Maarten and is one of four constituent countries that form the Kingdom of the Netherlands.  The northern French half comprises the Collectivité de Saint-Martin (Collectivity of St. Martin) and is an overseas collectivity of France.

On January 1, 2007 the population of the entire island was 74,852 inhabitants, 38,927 of whom lived on the Dutch side, and 35,925 on the French side.  Collectively, the two territories are known as "St-Martin / St Maarten".  Sometimes SXM, the IATA identifier for Princess Juliana International Airport (the island's main airport), is used to refer to the island.