Competencies needed by teachers who provide language and literacy instruction to English learners (ELs), including bilingual education, English as a second language, general education, and special education teachers, are outlined. The competencies suggest a shared knowledge base all teachers of ELs must have to provide linguistically and culturally responsive instruction and intervention that is differentiated to meet students' language-, literacy-, and/or disability-related needs. Implications for teacher education programs are discussed, highlighting the importance of interdisciplinary collaboration in teacher preparation.