To address conceptual and methodological shortcomings in the extant literature on student mobility, this study employs event history modeling to describe and explain how state policy levers, specifically state grant aid, relates to mobility and baccalaureate degree completion. We find that state grant aid reduces mobility, but less so than institutional grant aid. We also find that regardless of the form of mobility, it was negatively related to degree completion. This inquiry contributes to work on student mobility, (e.g., McCormick, Transfer behavior among beginning postsecondary students: 1989-94, Tinto, Rev Educ Res 45(1): 1975) by conceptualizing persistence as student flow within and between institutions; and offers a conceptual tool for policy makers seeking to improve college completion.Keywords Student flow Á Event history analysis Á Educational attainment Á Financial aid Á Grants Student mobility-the movement of students into and through postsecondary educationis of growing importance in higher education. Prompted in part by the Obama administration's espousal of the 2020 goal (i.e., to have the highest proportion of college graduates in the world), numerous advocacy, research, policy, and philanthropic organizations have launched broad initiatives focused on getting more students into and through higher education (Russell 2011). These initiatives are being implemented in a context where student pathways through higher education are increasingly diverse and complex. This