The Mesoamerican Barrier Reef System (MBRS), extending from Isla Contoy on the north of the Yucatan Peninsula to the Bay Islands of Honduras, includes the second longest barrier reef in the world. It is approximately 1,000 km long and spans over four countries and two trans-boundary areas: Chetumal Bay, between Belize and Mexico; and the Gulf of Honduras, between Belize, Guatemala and Honduras. The MBRS is unique in the Western Hemisphere due to its length, composition of reef types, and diverse assemblage of corals and related species. The MBRS contributes to the stabilization and protection of coastal landscapes, maintenance of coastal water quality, and serves as breeding and feeding grounds for marine mammals, reptiles, fish and invertebrates, many of which are of commercial importance. The MBRS is also of immense socioeconomic significance providing employment and a source of income to an estimated one million people living in adjacent coastal areas.