While much of the literature regarding Spanish as a heritage language has focused on higher education institutions and areas of traditional immigration in the United States, less research has specifically examined Spanish heritage language learner (HLL) policies in states like Tennessee that have recently experienced an exponential rise in the number of Spanish HLLs in schools. Through 22 in-depth qualitative interviews, this study examines how high school teachers negotiated their institutions' Spanish HLL policies (or lack of them) and how this negotiation informed the implementation of the policies in classroom practices and curricula. Results indicate that teachers worked in a policy vacuum and exerted their agency by creating their own policies and taking initiatives to address issues related to identification, placement, and curriculum that were specific to their contexts and compatible with their pedagogical goals. The study concludes highlighting the importance of bottom-up language policy and planning in areas of recent immigration.