Alongside the increased presence of students classified as English learners (ELs) in mathematics classrooms exists a persistent pattern of the marginalization of ELs. Educators have sought research to identify how to provide ELs with high-quality mathematics education. Over the past two decades, education researchers have responded with increased attention to issues related to the teaching and learning of mathematics with ELs. In this review we analyzed literature published between 2000 and 2015 on mathematics teaching and learning with K-12 ELs. We identified 75 peer-reviewed, empirical studies related to the teaching and learning of mathematics with ELs in Grades K-12 and categorized the studies by focus (Learning, Teaching, and Teacher Education). We synthesize the results of these studies through the lens of a sociocultural perspective on language in mathematics. We then discuss avenues for future research and calls to action based on the extant body of literature.