Scholars contend that agency is at the heart of cultivating equitable learning spaces for all learners. While it is intuitive that literacy educators support agency during instruction, there is diverse terminology surrounding the concept of agency in the field. As a result, aligning the construct to instructional practices and developing a conceptual understanding of agency in practice has been challenging. Our research team completed a systematic literature review of agency during literacy instruction. In this article, we describe findings of this review of empirical research on agency in literacy spanning from 1975-2017. Findings highlight the complexities associated with defining agency as well as the need for diverse methodological approaches to examining agency in literacy contexts.