The vast amount of research conducted on student persistence over the past thirty years is indicative of the continuing and evolving interest in retention of students. Framed through multiple perspectives, this retention research is driven by the fact that more students leave institutions without graduating, year after year. Much more than an academic question, retention is of the utmost importance to universities and colleges; campus educators, institutional decision makers, and external constituents watch persistence and graduation rates closely. Fueled by the impetus to understand as well as affect persistence, this chapter employs a mixed-methods, longitudinal approach to explore the effects of a course intervention for undeclared students--a population often determined to be at risk of not persisting. The authors demonstrate the utility of such approaches in helping institutional researchers evaluate programmatic effects on students' persistence and graduation. (Contains 1 note.)