Concept maps (Cmaps) are still underutilized in adult literacy programs and classes. The teaching and learning approaches that have been used historically in adult literacy programs to address the learning needs of these students have not kept pace with the literacy skill demands that have sprung from the increased pace of technological innovation. This study investigated published reports of empirical research studies that have tested the effects of Cmaps on the achievement ability of a wide variety of learners. The literature review included 55 refereed journal articles. Our findings provide useful information for adult literacy practitioners interested in utilizing concept mapping as an approach to teaching and learning in their classes.