Task-based language teaching (TBLT) is a pedagogical approach that involves identifying real-world tasks that learners need to be able to do in the target language and then developing classroom-appropriate, context-specific versions of these tasks. In this paper, we use Long's methodological principles for TBLT to evaluate a task-based approach within two Indigenous language-teaching contexts: the Macuiltianguis Zapotec classroom in Oaxaca, Mexico, and a workshop for teachers of Salish Qlipse in the state of Montana. Throughout the article, we give special consideration to issues of investment in the target language, expanding on Norton's definition of language learner investment to argue that teacher and community investment in the language and language revitalization process are critical to the successful implementation of TBLT in Indigenous contexts.