As educators in academic programs featuring interdisciplinary learning, the authors can attest that helping undergraduate students in an interdisciplinary studies major engage in interdisciplinary learning--that is, draw from two or more disciplines to advance understanding of a problem, question, or phenomenon--is no mean feat. Consequently, the authors have witnessed their students struggle to complete interdisciplinary activities. Yet, they have also marveled at the quality of their interdisciplinary work, particularly that created by seniors. This observation prompted the authors to wonder when and how students in interdisciplinary studies programs develop as learners. To explore this question, they interviewed ten students enrolled in an interdisciplinary studies major each semester of their undergraduate experience and examined interview data for patterns in relation to student development theory, specifically Marcia Baxter Magolda's research on college students' intellectual and personal development. Data were collected from students enrolled in a self-designed interdisciplinary undergraduate program at a mid-size public institution. After reviewing interview data, the authors identified distinguishing features of students' experience. The authors describe and interpret students' experiences in the first year, middle two years and final year. The data from this longitudinal study offer a comprehensive look at the developmental journey experienced by students in one undergraduate interdisciplinary studies program. The study demonstrates the interpersonal and intrapersonal as well as the epistemological benefits of an engaged, interdisciplinary, and residential learning community, but it also provides a glimpse into students' developmental journey and processes of meaning-making across the undergraduate experience. (Contains 1 table.)