This chapter shares the effects of a multi-year project to integrate explicit pronunciation instruction into the curriculum of intermediate Spanish courses at a liberal arts undergraduate university. The pedagogical materials incorporate foundational linguistic principles, such as awareness of the expert unconscious knowledge of a speaker’s native language, an appreciation of the linguistic diversity present across cultures, and a scientific approach to creating and testing hypotheses about how a language works as part of L2 language learning. The authors and researchers found effects in L2 learning beyond the scope of these specific topics: students made connections from pronunciation to other areas of the grammar; students used their expert native language knowledge to recognize patterns in the L2; students demonstrated increased appreciation for dialectical diversity, including heritage speaker productions; and students demonstrated greater comfort with using the L2 more frequently and in more contexts. The chapter closes with a discussion of the benefits to instructors as well as some recommendations for how to incorporate linguistic foundations in other language classes.