The author states that one definition of "paradigm shift" is "the process whereby a governing conceptual framework becomes destabilized and is eventually replaced, more or less wholesale, by a new conceptual consensus." He asks whether recent fundamental changes in academic medicine amount to a paradigm shift, and then briefly describes and comments on 25 changes under way in academic medicine (e.g., the growing importance of cost considerations; focus on episodic care of the acutely ill individual moving instead toward clinical and fiscal responsibility for the health of a population; relative autonomy of the physician evolving to increasing interdependence, both clinical and financial). The author maintains that the basic conceptual framework of academic medicine's core mission--patient care, teaching, and research--remains the same, and that this mission's capacity for good has greatly grown in recent decades. Over the same interval the core business of academic medicine (i.e., its financing) and how that relates to the core mission have indeed become destabilized. These also comprise a "conceptual framework" by which academic medicine has functioned, and that framework is being replaced, compellingly, by what amounts to a new conceptual consensus--in short, a paradigm shift. He urges his colleagues in academic medicine to be clear-eyed, responsive, and innovative, and never to give up as they work to forge a new and sustainable system that maintains and strengthens scholarship and service.