The Smithsonian Tropical Research Institute (STRI, Spanish: Instituto Smithsonian de Investigaciones Tropicales) is located in Panama and is the only bureau of the Smithsonian Institution based outside of the United States. It is dedicated to understanding the past, present, and future of tropical ecosystems and their relevance to human welfare. STRI grew out of a small field station established in 1923 on Barro Colorado Island in the Panama Canal Zone to become one of the world's leading tropical research organizations. STRI's facilities provide for long-term ecological studies in the tropics and are used by some 1,200 visiting scientists from academic and research institutions around the world every year.