A primary concern affecting the more than 300 American Indian tribes and their educational institutions is the promotion, maintenance, and preservation of their approximately 200 native languages. The nature of language use must be documented and assessed to ascertain whether tribal members, particularly children, possess native language skills consistent with the body of knowledge that tribal communities wish to pass to future generations. The guide presents factors for American Indian language groups to consider when selecting and/or refining existing instruments and developing new instruments for assessing oral language proficiency including: documenting language usage among community members and the sequence of child language acquisition; identifying phonological, syntactic, and semantic components of a language; defining proficiency; determining dimensions of bilingual measurement; considering cultural, age, linguistic, and technical appropriateness of testing instruments; establishing a language data base; choosing testing approaches (discrete point, integrated, direct rating, self-rating, or observation) and techniques (natural communication or linguistic manipulation); developing instrument administration skills; and pilot testing, field testing, and norming instruments. The report includes: a map locating Arizona Indian reservations and languages, names and addresses of 32 resource linguists for Yuman, Athabascan, and Uto-Aztecan languages; sources for 3 current American Indian Language Assessment Instruments; and a 60-item bibliography. (NEC)