With this volume, the editors' goal is to offer an accessible resource, long-awaited by educators whose individual instructional practice and/or institutional paradigm shifted to a more collaborative approach to language education. Through this collection of chapters, the contributing authors closely examine ESL/EFL coteaching and other collaborative practices by (a) exploring the rationale for teacher collaboration to support ESL/EFL instruction, (b) presenting current, classroom-based, practitioner-oriented research studies and documentary accounts related to co-teaching, co-planning, co-assessing, curriculum alignment, teacher professional development, and additional collaborative practices, and (c) offering authentic teacher reflections and recommendations on collaboration and co-teaching. These three major themes are woven together throughout the entire volume, designed as a reference to both novice and experienced teachers in their endeavors to provide effective integrated, collaborative instruction for EFL or ESL learners. This volume will help preservice and inservice ESL/EFL teachers, teacher educators, professional developers, ESL/EFL program directors, and administrators to find answers to critical questions about collaborative practices.