This article notes an enduring ambivalence in medical sociology concerning the epistemology and ontology of disease and shows this is precisely an ambivalence concerning whether biomedical disease categories are best understood as topics of, or as resources for, medical sociological research. The first section critically reviews the topic/resource debate in ethnomethodology. The second section elaborates upon the pertinence of this debate to sociological debates directly concerned with the epistemology and ontology of disease. The article concludes by demonstrating how framing the epistemology and ontology of disease in terms of the topics and resources of medical sociological analysis serves to clarify the work of thinking sociologically about disease and helps overcome protracted theoretical challenges that have persistently troubled medical sociological research.