We investigate how established professionals manage their identities in the face of identity threats from a contested shift in the professional logic that characterizes their field. To do so, we draw on interviews with 113 physicians from five European transition countries who faced pressure for change in their professional identities due to a shift in the logic of health care from a "narrow specialism" in primary care, which characterized the Soviet health system, to "generalism," which characterizes primary care in the West. We found three important forms of professional identity threats experienced by physicians during this period - professional values conflict, status loss, and social identity conflict. In addition, we identified three forms of identity work - authenticating, reframing, and cultural repositioning - that professionals who successfully transitioned to the new identity performed in order to reconstruct their professional identities so that they were aligned with the new logic. Based on these findings, we present a model of how established professionals change their professional identities as a result of a contested shift in the professional logic of their field, and discuss the underlying mechanisms through which this occurs.