BirdLife International is a global partnership of conservation organizations and research institutions that work to conserve birds, their habitats and global biodiversity by working with people toward the sustainable use and management of natural resources. The partnership is made up over 100 national conservation organizations throughout the world, an international secretariat located in Cambridge, U.K., and regional offices in Europe, Asia, Africa, the Middle East and the Americas. There are 16 BirdLife partners in the Americas including the National Audubon Society in the United States. Nature Canada and Bird Studies Canada are the BirdLife partners in Canada. The main focus of BirdLife International's habitat conservation objectives is the Important Bird Area (IBA) Program. By working with partner organizations, BirdLife's IBA Program seeks to identify and protect sites critical for birds throughout their biogeographic ranges. Sites that are critical for the long-term survival of bird populations have been identified across the globe using internationally agreed upon scientific criteria.