Preface / Bogum Yoon -- Part I: Overview and theoretical perspectives -- 1. Introduction: The need of teacher collaboration for ELLs / Bogum Yoon -- 2. Theoretical perspectives of teacher collaboration / Bogum Yoon -- Part II: Case examples in K-12 settings and across curricula -- 3. Both teachers' names are on the door: ESL and classroom teacher collaboration / Christine Uliassi -- 4. Reflections on co-teaching and collaboration: communication, flexibility, and congruence / Heeok Jeong and Laura Eggleston -- 5. Reimagining collaboration: exploring how ESL teachers and technology coach perceive collaboration to improve ELLs' language skills / Ana Vintan and Tiffany L. Gallagher -- 6. "Leadership roles at different points": collaborating to plan for and teach ESL students in a secondary social studies classroom / Amanda Giles -- 7. "I see myself as another teacher": co-teaching practice for ELLs in a science class / Min Wang and Daniel Ness -- 8. Co-taught integrated language and mathematics content instruction for multilingual learners / Carrie McDermott and Andrea Honigsfeld -- 9. Collaboration for culturally relevant pedagogy: an extended project involving content and ESL teachers / Yvonne Pratt-Johnson -- Part III: Implications and suggestions for future research and practice on teacher collaboration -- 10. What can a principal do to support teacher collaboration for ELLs? Implications for building leadership practice / Suzanne E. Mcleod -- 11. Implications and suggestions for effective teacher collaboration for ELLs / Bogum Yoon