Since its inception at the turn of the last century, adult education English as a Second Language (ESL) instruction in the United States has been entwined with immigration processes and ideas of the nation. In spite of current uncertainty about the overhauling of federal immigration policy, increasingly anti-immigrant laws in states such as Arizona, and attempts to restrict immigration in cities like Hazelton, Pennsylvania, demand for ESL instruction continues to be the fastest-growing sector of adult basic education. Adult educators need to know about the origins of English-language teaching in the United States because the past can reveal ways to better shape the future. This article offers a history of adult education ESL instruction in the United States, followed by a discussion of key issues in the immigration literature that impact adult educators and their work in program development and classroom teaching.