Temporary doctors (locum tenens) have always been a small, but often life-saving, element of medical staffing. But in the fast-growing field of hospital medicine, where demand outstrips supply, some communities have come to depend on a “permanent” revolving door of locum hospitalists. This article explores the pros and cons of that practice and questions the conventional wisdom that locum tenens is often the only–and best–way to staff fledgling hospitalist programs. Drawing from interviews with multiple hospitalists, recruiters and consultants, the story lays out some major short- and long-term ramifications of hospital medicine’s reliance on locum tenens staffing, including the economic viability of groups and hospitals, the quality of clinical care provided to hospitalized patients, and the professional reputation of this new medical specialty.