This study examines the strategies of the biomedical discourse vis-à-vis the growing public demand for alternative medicine by comparing formal and informal claims for jurisdiction. The analysis is based on two main sources of data from Israel: (a) two formal position statements, and (b) a series of participant observations and interviews with practitioners in clinical settings where biomedical and alternative practitioners collaborate. At the formal level, the biomedical discourse seeks to secure its dominant position by drawing strict cognitive and moral lines differentiating “proper biomedicine” from “improper alternative medicine.” At this level alternative medicine appears morally “contaminated” and its knowledge-base delegitimized by extreme forms of boundary-work. At the informal level, the contour of boundaries change. In the hospital field where alternative and biomedical practitioners are collaborating, mutual respect was expressed even as social and symbolic boundaries were being demarcated. Modifying the forms of boundary-work appears to be biomedicine's reactive strategy in the field to changing environmental and market demands. It is a strategy that allows biomedical discourse to absorb its competitor within its professional jurisdiction with no battle, while retaining absolute epistemological hegemony and Institutional Control.