Urban schools, noted for their diverse student populations and variety of instructional resources and personnel, often are challenged in providing a coherent and differentiated instructional program for the wide array of learners served. In this article, we describe coteaching instructional models to support ELL students in elementary general education classrooms. ELL and general education teachers collaborated in planning, teaching, and reflecting on their instruction. Despite an expedited timeline for implementation and decreased personnel resources in the 2nd year of the study, collaborative teaching relationships were productive and rewarding. Of greatest importance, ELL student achievement increased substantially. Implications for practice include building the knowledge that supports collaboration, strategically allocating instructional personnel, and providing ongoing opportunities for collaborative learning and development. (Contains 2 figures, 2 tables and 1 footnote.) [Research for this article was supported by the Office of Special Education Programs.]