Policy makers and education researchers emphasize the need for English learners to develop academic language in order to improve school achievement. However, little work has been done to understand how academic language, conceptualized in English-only environments, is pedagogically relevant for prospective bilingual teachers who have experienced subtractive schooling (Valenzuela, 1996). This article presents a critical interpretive review of studies that explore Spanish development in bilingual teacher candidates who are Heritage Spanish Speakers (HSS). Our analysis of 36 studies found two main obstacles and three types of solutions towards Spanish development in bilingual teacher preparation programs. Obstacles coalesced around structural and ideological dimensions. Solutions pointed to three pathways for Spanish academic language development: content-based instruction, sociolinguistic approaches, and socio-symbolic transformations. Of the 36 articles, 20 aligned with solutions and 16 with obstacles. Our conclusions point to linguistic and cultural factors specific to Spanish-speaking communities in the United States that deserve more careful attention as part of policy-driven pedagogical improvement efforts. Based on our findings, we discuss the ambivalent experiences impinging on bilingual teacher candidates who are HSS, the implications of prevailing decontextualized approaches, and the need to further theorize the construct of academic Spanish.