SIL International, previously the Summer Institute of Linguistics, has for over 50 years investigated the world's lesser known languages, many of which are spoken in pre-literate societies. Because the people who speak these languages frequently live in social and and economic isolation, the research most often is conducted among the poorest of the world's poor.

In the pursuit of studying these undocumented minority languages, many disciplines are brought to bear, particularly linguistics and anthropology. So far, SIL has investigated 1320 languages, spoken by 350 million people in more than 50 countries. SIL does not stop with recording and analyzing languages, but is also engaged in literacy programs under the sponsorship of local, regional and national organizations. They provide linguistic training and develop projects in community service.

In addition to the usual activities of researchers in linguistics, SIL is also interested in ethnomusicology, where they not only document the musics around the world, but also promote the use of indigenous music in the context of contemporary society.