Teacher professional learning (TPL) can function as a powerful resource in supporting culturally sustaining educational practices for multicultural and multilingual students. However, as this chapter discusses through a detailed description of the literature, the design of current TPL initiatives often leads to a perpetuation of top down discourses about the role of teachers and bilingual learners in K-12 contexts. To speak to these challenges, the chapter provides readers with a detailed account of a bilingual National Science Foundation (NSF)-funded model of professional learning that could serve as an alternative culturally sustaining model for TPL. Specifically, the goal of the NSF initiative was to position in-service ESOL and science teachers of English as agentive and culturally responsive in their work. The systemic functional linguistic paradigm that undergirded the initiative placed emphasis on incorporating students' linguistic and experiential repertories in co construction of knowledge. This chapter concludes with recommendations for the field.