Having enjoyed tremendous growth for the past 5 years, the anti-aging medicine movement is redefining aging so that it becomes a target for biomedical intervention. Targeting aging for intervention dislodges popular understandings of aging: for anti-aging practitioners it no longer matters if aging is natural since it can be itself the target of therapy. So-called "age-associated" diseases like cancer are, in this framework, conceived of as symptoms of aging. Anti-aging medicine is a broad term that may comprise groups selling remedies over the Internet, companies touting the "anti-aging"ness of their products, practitioners who work outside of scientific medicine, and practitioners of anti-aging medicine in clinics who believe that their work is strictly scientific. This article, drawing from more than 3 years of ethnographic interviews, participant observation in clinics and conferences, and a review of the literature, considers the last group. It examines the involvement stories of anti-aging medicine practitioners in two Western United States metropolitan cities. These stories reflect the practices of anti-aging medicine practitioners and the accompanying rationale for involvement. Often originally patients themselves, practitioners frame their involvement with the anti-aging movement in three ways. First, they describe aging as it is currently experienced as a time of decline, suffering, and weakness. This anguish is not inevitable, they argue, and their work toward treating aging biomedically is situated as clearly moral. Secondly, intense frustration with the current biomedical environment has motivated practitioners to look for other ways in which to practice: anti-aging medicine is their chosen alternative. Finally, with dramatic expectations of future biotechnologies and disdain for current medical treatments of old age, anti-aging practitioners embrace a scientific revolutionary identity. These stories of migrations from patient to practitioner reveal the values upon which this movement is grounded and how coming to be a part of it is as much about the movement's mission as it is the origins of the migrations.