This conference uses the particular case study of astrology as a means to study the broader implications of boundary-work. It examines the intersections among science, the occult, and the religious cultures that lived in the medieval Islamic world—including Islam, Judaism, Christianity, and Zoroastrianism. The conference hopes to complicate the categories of magic, science, and religion by looking at how boundaries between these fields were articulated by medieval scholars. Boundary-work, by its very nature, is interdisciplinary; the conference will bring together scholars of religious studies, history, sociology, art, and science studies to collectively examine the chosen case study of astrology. By looking at practices of, categorizations of, and debates surrounding astrology in the medieval Islamic world, the conference hopes to shed light on the broader questions of when, where, why, and how definitions and boundaries are established between science, magic, and religion.