In this article I invite a reconceptualization and expansion of the field of second language acquisition (SLA) by examining possible intersections between SLA and the area of language instruction currently referred to as the teaching of heritage languages. I discuss the ways in which the opportunity of broadening SLA-and-instruction research can be seized by current researchers so that it can address the most intractable educational problems involving language. Drawing from current research on bilingualism, I first describe the challenges of providing language instruction for heritage speakers and examine the bilingualism of these unique language learners. I then offer an overview of the questions raised by the study of heritage language learners. Finally, I describe communities of professional practice and existing disciplinary boundaries and conclude with a discussion of the ways in which the field of SLA can draw from other areas in order to affect the educational futures of language minority children around the world and, at the same time, contribute to our greater understanding of the human language faculty.