This article presents a case study of a recent controversy over the use of computed tomography (CT) as a diagnostic technology in South Korean hospitals. The controversy occurred in the wake of a series of conflicts in the late twentieth century over the legitimate placement of healing practices, medicinal substances, and medical technologies within Korea’s separate "Western Medicine" (WM) and "Korean Medicine" (KM) systems of health care and pharmaceutical distribution. The controversy concerned an attempt to use hi-tech imaging technology—the epitome of modern medicine—in a clinic that maintains a strong ideological attachment to Korean healing traditions. A close study of this dispute, based on interviews, participant observation, and documentary analysis, showed that discursive positions taken about the translatability of medical technologies changed with the context of dispute, and did not reflect a stable epistemic boundary between rival medical paradigms.