A distinguishing feature of English learners (ELs) centers on coming from homes in which a language other than or in addition to English is used, but bilingualism itself is not a risk factor for low academic achievement. Yet in the United States, ELs' reading achievement continues to lag behind that of their English-proficient peers. In this introduction, I discuss the need for research that centers the role of language comprehension among ELs for understanding and supporting their literacy achievement, highlight some of the key contributions made by the authors of articles that comprise this special topic collection, and offer several avenues that are ripe for future research.