This is an introduction to a special issue on capstone courses, which describes a range of models, common goals across capstones, popular teaching methods used in capstones, the value of capstones as a way to assess a curricular program, and issues related to faculty development. The curricular focus, mathematics, is somewhat unique and so may be especially useful for instructors who come with a strong disciplinary connection and are unsure of how capstones may fit into or enhance the content they hope to impart on students. An interesting and also unique aspect of this piece is the acknowledgement of capstones’ value in program assessment. For administrators in particular, this may be a helpful argument for an added benefit of capstones beyond student learning directly associated with the course. This article, as with several others, is explicit in framing the teaching of capstones as more of a mentorship relationship–an idea that would be worth following up on in future research.