Many educators and policymakers look to two-way dual language immersion as one of the most promising options to close achievement gaps for English learners. However, the programs' effectiveness depends on the quality of their implementation. This article reports on a large-scale study of the implementation of dual language immersion across a large, urban school district. Using classroom observations, we examined teaching practices and language use by teachers and students in dual language immersion classrooms across an entire school district. We found strong implementation of teaching practices consistent with sheltered instruction, and strong adherence by teachers to partner language use as prescribed by the district's guidelines. This article provides a descriptive view of what is happening in two-way dual language immersion classrooms in a large, urban U.S. school district. While other studies may examine classroom practices, few have done so on this scale. [This report was published in "International Multilingual Research Journal" (EJ1088159).]