Teachers of English as a second language (ESL) are often on the frontline of working with adult ESL learners who are facing a difficult developmental pathway to academic and/or economic success. These learners come to the task of learning English with widely varying schooling experiences, degrees of first language literacy, and English language proficiency. A workplace that increasingly demands considerable content knowledge, critical thinking abilities, and excellent communication skills has led to a greater emphasis on academic skill development from the earliest stages of literacy and language learning, and has highlighted a need for continuing this emphasis for those transitioning into vocational or academic studies. A known but not often implemented approach to adult ESL learning, content-based instruction, is a viable response to this situation. Content other than language is common in ESL materials, but making learners accountable for actually learning this content is often secondary to language skill development, if considered at all. However, learning the content naturally motivates deep processing of language and the use of higher order thinking skills, which are foundational for high levels of literacy. This article provides teachers of adult ESL learners, vocationally or academically oriented, with the rationale, guiding principles, and examples of that focus on content learning through text-engaging tasks.