Objective: Quantway is a Carnegie Math Pathways initiative, which redesigns the content, pedagogy, and structure of traditional developmental mathematics courses to simultaneously tackle traditional barriers to student success and support a broad range of developmental students in achieving their mathematics potential. Specifically, Quantway is a quantitative reasoning sequence that is comprised of a single term accelerated developmental mathematics course called Quantway 1 and a college-level mathematics course called Quantway 2. This study assesses the effectiveness of the developmental mathematics course, Quantway 1, during its first six semesters of implementation. Method: We used a hierarchical linear modeling technique to conduct propensity score matching across 37 student characteristics to compare the course performance of Quantway 1 students with matched comparison students from traditional developmental mathematics courses. Results: Quantway 1 students demonstrated significantly higher odds of success in fulfilling developmental mathematics course requirements and enrolling in college mathematics courses in the following year than matched comparison students. In addition, Quantway 1 effects were positive across all sex and race/ethnicity subgroups as well as in nearly all classrooms and colleges. Contributions: This study provides robust evidence that Quantway 1 increases student success in fulfilling developmental mathematics requirements and advances equity in student outcomes. Implications of and future directions for the Pathways are discussed.