The Plains Indian Sign Language (PISL) Corpus Linguistic Project will demonstrate how indigenous sign language serves as an alternative to spoken language among deaf and hearing tribal members. Since PISL and other indigenous language varieties in the corpus are endangered, additional documentary linguistic work is critical to advance our knowledge of the cognitive, cultural, and linguistic underpinnings of indigenous signed language varieties and to the survival of these languages. The project objectives are to: 1) transform an extensive collection of PISL documentary linguistic materials into a digital corpus that is accessible to local Native American communities and scholars of linguistics and anthropology, and related disciplines; 2) identify and involve more American Indians who are learning and using indigenous sign language varieties in order to generate linguistic descriptions about sign language usage, lexicon, and grammar; 3) collaborate with expert signers from different American Indian nations; 4) collect additional documentary materials of indigenous signing from archival and contemporary fieldwork; 5) increase awareness about sign language in intertribal and international communities; and 6) disseminate project outcomes to Native American communities, broader audiences, and researchers of indigenous and endangered languages. The digital corpus will contribute to training students in field methods, linguistic analyses, emergent technologies, and engage members of Native communities in documenting and revitalizing their languages. (Edited by staff)